Forum: War Ensemble BBS

DAY1SVR: Day 1 Convective Outlook

From COD Weather Processor @1:2320/107 to All on Wed Jul 15 12:02:48 2026

ACUS01 KWNS 151202
SWODY1
SPC AC 151200

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0700 AM CDT Wed Jul 15 2026

Valid 151300Z - 161200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE MID-ATLANTIC...NORTHERN NEW ENGLAND...NORTHERN ROCKIES/HIGH PLAINS...PACIFIC NORTHWEST...ARIZONA...AND SOUTH-CENTRAL TEXAS...

...SUMMARY...
There is a conditional risk for severe thunderstorms capable of
producing large hail and damaging winds across parts of the
Mid-Atlantic this afternoon and evening. Isolated damaging winds
appear possible for portions of northern New England, the northern
Rockies/High Plains, Pacific Northwest, and Arizona. A brief tornado
or two may also occur across parts of south-central Texas.

...Mid-Atlantic...
Hot temperatures are forecast south of a front that will be draped
across southern New England into the northern Mid-Atlantic by peak
afternoon heating. Coupled with dewpoints in the upper 60s to low
70s, this will contribute to a moderately unstable airmass, with
MLCAPE of 1500-2500 J/kg probable. The strongest mid-level height
falls/forcing for ascent associated with a shortwave trough over
Ontario/Quebec into New England are expected to remain generally
north of the surface front. Therefore, robust convective development along/south of the boundary in the northern Mid-Atlantic remains
highly uncertain. Another factor that could limit thunderstorm
initiation is the potential for more muted instability across the
warm sector due to smoke from upstream wildfires.

With continued uncertainty regarding initiation, have maintained the
Marginal Risk across the Mid-Atlantic with no changes. However, on
the condition that surface-based thunderstorms develop, the presence
of seasonably strong mid-level winds and resultant 40-50+ kt of
effective bulk shear would support supercells/multicells capable of
both severe hail and damaging winds.

...Northern New England...
Within the zone of strongest forcing for ascent associated with a
mid-level shortwave trough moving quickly eastward from southern
Ontario/Quebec into New England today, a band of low-topped showers
and thunderstorms may develop during the afternoon in a weakly
unstable environment. Steepening low-level lapse rates, a unidirectional/westerly wind profile with height through mid levels,
and 30-40 kt of flow around 1-2 km AGL will support the potential
for locally damaging wind gusts, assuming convection develops and
can become surface based.

...Northern Wyoming into Southern Montana...
A weak/embedded mid-level vorticity maximum evident on water vapor
satellite imagery over the northern Great Basin this morning will
move northeastward today across the northern Rockies and adjacent
High Plains. Diurnal heating across the higher terrain coupled with
the glancing influence of this subtle disturbance should foster the
development of scattered afternoon thunderstorms. Weak to moderate
instability is forecast, with a relatively deep and well-mixed
boundary layer across lower elevations. Recent guidance continues to
show some potential for upscale growth into a loosely organized
cluster with cold pool organization and a risk for isolated severe
wind gusts into the evening. However, the overall severe threat
should be tempered by modest deep-layer shear.

...Pacific Northwest...
Isolated to scatted thunderstorms should develop this afternoon
along and east of the Cascades from central OR into southern WA.
This convection will be aided by orogrpahic influences and modest
large-scale ascent preceding a closed upper low off the coast of the
Pacific Northwest. Recent NAM/RAP forecast soundings show a deeply
mixed boundary layer developing across this region through peak
afternoon heating, with weak MLCAPE present. Enhanced southwesterly
mid-level flow should support sufficient deep-layer shear for some
updraft organization, and isolated severe gusts may occur with the
stronger cores as they spread north-northeastward through the
evening.

...Arizona...
Weak east-northeasterly mid-level flow is forecast today across AZ
on the southern periphery of upper ridging extending across much of
the central CONUS. Daytime heating of a seasonably moist low-level
airmass across southern/central AZ will yield weak to moderate
instability by mid afternoon with a very well-mixed boundary layer.
This environment should support isolated strong to severe gusts as
convection initially develops over the Mogollon Rim and higher
terrain of southeast AZ, before subsequently spreading westward into
the lower deserts. However, a more organized severe wind threat will
likely be limited by weak deep-layer shear.

...South-Central Texas...
A weak mid-level low over southwest TX this morning should make only
slow westward progress through the period across the southern High
Plains. Modest winds at low levels veer to southwesterly with height
at mid levels per recent VWPs from KDFX/KEWX. Up to 100 m2/s2 of 0-1
km SRH may be sufficient for some low-level rotation and perhaps a
brief tornado or two with ongoing convection given a very moist
low-level airmass. This threat may continue through the day as the
boundary layer gradually destabilizes with filtered daytime heating.

..Gleason.. 07/15/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Wed Jul 15 16:33:34 2026

ACUS01 KWNS 151633
SWODY1
SPC AC 151631

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1131 AM CDT Wed Jul 15 2026

Valid 151630Z - 161200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE MID-ATLANTIC...NORTHERN NEW ENGLAND...NORTHERN ROCKIES/HIGH PLAINS...PACIFIC NORTHWEST...ARIZONA...AND SOUTH-CENTRAL TEXAS...

...SUMMARY...
There is a conditional risk for severe thunderstorms capable of
producing large hail and damaging winds across parts of the
Mid-Atlantic this afternoon and evening. Isolated damaging winds
appear possible for portions of northern New England, the northern
Rockies/High Plains, Pacific Northwest, and Arizona. A brief tornado
or two may also occur across parts of south-central Texas.

...Northern Mid-Atlantic into the Northeast...
Recent surface analysis places a cold front from northern ME
southwestward into northern NY before arcing westward across
southeastern Ontario and west-northwestward across northern MI and
far northern WI into central MN. Eastern portion of this front is
expected to push southeastward through the Northeast today, moving
ahead of a low-amplitude and progressive shortwave trough currently
moving through eastern Ontario into far southern Quebec. Large-scale
ascent associated with this wave will spread across the region, but
warm temperatures aloft will likely limit thunderstorm coverage
across much of the region. A band of low-topped showers and
isolated/brief thunderstorms may develop during the afternoon
across northern New England, where forcing for ascent will be the
strongest. Overall buoyancy will be modest, but steepening low-level
lapse rates, a unidirectional/westerly wind profile with height
through mid levels, and 30-40 kt of flow around 1-2 km AGL will
support the potential for locally damaging wind gusts.

Farther south in the northern Mid-Atlantic, warm and moist
conditions will persist south of the front. However, warm mid-level temperatures may prevent the airmass from fully destabilizing, with
lingering convective inhibition likely. Given this inhibition and
displacement farther south of the stronger forcing for ascent,
robust convective development remains highly uncertain.
Additionally, residual smoke could also limit heating, keeping
convective inhibition in place. That being said, strong deep-layer
westerly flow and steep mid-level lapse rates would support strong
outflow and perhaps even isolated hail with any storms that can
develop and mature.

...Northern Wyoming into Southern Montana...
Recent satellite imagery shows a weak vorticity maximum over eastern
ID. This vorticity max is forecast move northeastward today across
the northern Rockies and into the adjacent northern High Plains.
Diurnal heating across the higher terrain coupled with
the glancing influence of this subtle disturbance should foster the
development of scattered afternoon thunderstorms. Weak to moderate
instability is forecast, with a relatively deep and well-mixed
boundary layer across lower elevations. Scattered thunderstorm
coverage could result in some upscale growth into a loosely
organized cluster with cold pool organization, and a risk for
isolated severe wind gusts into the evening. However, the overall
severe threat should be tempered by modest deep-layer shear and
limited storm duration.

...Pacific Northwest...
Multiple rounds of isolated to scattered thunderstorms are possible
this afternoon along and east of the Cascades from central OR into
southern WA. The first round during the afternoon will be aided by
orographic influences and a weak shortwave trough preceding a closed
upper low off the coast of the Pacific Northwest. High cloud bases
and a deeply mixed boundary layer will support the potential for a
few strong gusts with this activity. Another round of storms is
possible later this evening/overnight as another weak shortwave
trough rounds the upper low as the low itself also drifts closer to
the coast. Very dry low to mid-levels will persist throughout the evening/overnight, with the potential for isolated strong gusts
remaining possible.

...South-Central Texas...
Weak mid-level low over south-central TX will only drift slightly
westward today, remaining largely in place within the very moist
airmass over the region. Recent EWX VAD profiles show about 30 kt of
southerly flow between 1-3 km along the eastern periphery of this
low. Resulting hodographs show just enough low-level curvature to
support brief tornadoes given the tropical airmass in place.

...Arizona...
Weak east-northeasterly mid-level flow is forecast today across AZ,
which is on the southern periphery of upper ridging extending across
much of the central CONUS. Daytime heating of a seasonably moist
low-level airmass across southern/central AZ will yield modest
instability by mid afternoon. Initial development is anticipated
over the Mogollon Rim and higher terrain of southeast AZ, before
subsequently spreading westward into the lower deserts. A deeply
mixed boundary layer across the lower elevations could support
isolated strong to severe gusts.

..Mosier/Squitieri.. 07/15/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Wed Jul 15 19:48:36 2026

ACUS01 KWNS 151948
SWODY1
SPC AC 151946

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0246 PM CDT Wed Jul 15 2026

Valid 152000Z - 161200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE MID-ATLANTIC...NORTHERN NEW ENGLAND...NORTHERN ROCKIES/HIGH PLAINS...PACIFIC NORTHWEST...ARIZONA...AND SOUTH-CENTRAL TEXAS...

...SUMMARY...
There is a conditional risk for severe thunderstorms capable of
producing large hail and damaging winds across parts of the
Mid-Atlantic this afternoon and evening. Isolated damaging winds
appear possible for portions of northern New England, the northern
Rockies/High Plains, Pacific Northwest, and Arizona. A brief tornado
or two may also occur across parts of south-central Texas.

...20z Update...
The previous forecast remains on track with only minor adjustments
made, predominately across southern Montana where guidance has
trended towards a slightly higher coverage of thunderstorms within
an environment favorable for strong/severe winds. These trends are
supported by recent MRMS mosaics which depict convection developing
along the WY/MT border (see MCD #1624 for additional information).

...Texas...
Although thunderstorm coverage has been decreasing since late
morning across portions of central/southern TX, recent VWP
observations continue to show a strongly sheared environment across
the greater San Antonio area with 0-1 km SRH on the order of 100-200
m2/s2. Additionally, clearing skies and warming temperatures are
contributing to destabilization across parts of the region, and lift
associated with a departing mid-level wave continues to influence
the region. Consequently, some potential remains for organized
convection through late afternoon. Diminishing wind fields through
the evening should gradually diminish the severe threat tonight.

See MCD #1625 and the previous discussion below for additional
forecast details.

..Moore.. 07/15/2026

.PREV DISCUSSION... /ISSUED 1131 AM CDT Wed Jul 15 2026/

...Northern Mid-Atlantic into the Northeast...
Recent surface analysis places a cold front from northern ME
southwestward into northern NY before arcing westward across
southeastern Ontario and west-northwestward across northern MI and
far northern WI into central MN. Eastern portion of this front is
expected to push southeastward through the Northeast today, moving
ahead of a low-amplitude and progressive shortwave trough currently
moving through eastern Ontario into far southern Quebec. Large-scale
ascent associated with this wave will spread across the region, but
warm temperatures aloft will likely limit thunderstorm coverage
across much of the region. A band of low-topped showers and
isolated/brief thunderstorms may develop during the afternoon
across northern New England, where forcing for ascent will be the
strongest. Overall buoyancy will be modest, but steepening low-level
lapse rates, a unidirectional/westerly wind profile with height
through mid levels, and 30-40 kt of flow around 1-2 km AGL will
support the potential for locally damaging wind gusts.

Farther south in the northern Mid-Atlantic, warm and moist
conditions will persist south of the front. However, warm mid-level temperatures may prevent the airmass from fully destabilizing, with
lingering convective inhibition likely. Given this inhibition and
displacement farther south of the stronger forcing for ascent,
robust convective development remains highly uncertain.
Additionally, residual smoke could also limit heating, keeping
convective inhibition in place. That being said, strong deep-layer
westerly flow and steep mid-level lapse rates would support strong
outflow and perhaps even isolated hail with any storms that can
develop and mature.

...Northern Wyoming into Southern Montana...
Recent satellite imagery shows a weak vorticity maximum over eastern
ID. This vorticity max is forecast move northeastward today across
the northern Rockies and into the adjacent northern High Plains.
Diurnal heating across the higher terrain coupled with
the glancing influence of this subtle disturbance should foster the
development of scattered afternoon thunderstorms. Weak to moderate
instability is forecast, with a relatively deep and well-mixed
boundary layer across lower elevations. Scattered thunderstorm
coverage could result in some upscale growth into a loosely
organized cluster with cold pool organization, and a risk for
isolated severe wind gusts into the evening. However, the overall
severe threat should be tempered by modest deep-layer shear and
limited storm duration.

...Pacific Northwest...
Multiple rounds of isolated to scattered thunderstorms are possible
this afternoon along and east of the Cascades from central OR into
southern WA. The first round during the afternoon will be aided by
orographic influences and a weak shortwave trough preceding a closed
upper low off the coast of the Pacific Northwest. High cloud bases
and a deeply mixed boundary layer will support the potential for a
few strong gusts with this activity. Another round of storms is
possible later this evening/overnight as another weak shortwave
trough rounds the upper low as the low itself also drifts closer to
the coast. Very dry low to mid-levels will persist throughout the evening/overnight, with the potential for isolated strong gusts
remaining possible.

...South-Central Texas...
Weak mid-level low over south-central TX will only drift slightly
westward today, remaining largely in place within the very moist
airmass over the region. Recent EWX VAD profiles show about 30 kt of
southerly flow between 1-3 km along the eastern periphery of this
low. Resulting hodographs show just enough low-level curvature to
support brief tornadoes given the tropical airmass in place.

...Arizona...
Weak east-northeasterly mid-level flow is forecast today across AZ,
which is on the southern periphery of upper ridging extending across
much of the central CONUS. Daytime heating of a seasonably moist
low-level airmass across southern/central AZ will yield modest
instability by mid afternoon. Initial development is anticipated
over the Mogollon Rim and higher terrain of southeast AZ, before
subsequently spreading westward into the lower deserts. A deeply
mixed boundary layer across the lower elevations could support
isolated strong to severe gusts.

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Thu Jul 16 00:51:10 2026

ACUS01 KWNS 160050
SWODY1
SPC AC 160049

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0749 PM CDT Wed Jul 15 2026

Valid 160100Z - 161200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS CENTRAL TX...SOUTHERN/CENTRAL AZ...SOUTHEAST MT...AND PORTIONS OF CENTRAL OR
INTO SOUTHERN WA...

...SUMMARY...
Isolated damaging winds are possible for portions of the northern
Rockies/High Plains, Pacific Northwest, and Arizona into the early
overnight hours. A brief tornado or two may also occur across parts
of south-central Texas.

...Mid-Atlantic/Northeast...

Severe probabilities have been removed from the Northeast states
with the 01z update. The 00z OKX RAOB indicated ample inhibition,
which should suppress convection the remainder of the evening.
Despite strong deep-layer northwesterly flow and modest midlevel
lapse rates supporting elevated instability, it is unlikely
additional convection will develop overnight as a midlevel shortwave
impulse increasingly moves offshore over the Atlantic.

Some guidance suggests that convection ongoing over southern Lower
MI may continue to develop/percolate southeast overnight across Lake
Erie and into northeast OH/northwest PA within strong northwesterly
mid/upper flow. The 00z PIT RAOB shows steep lapse rates and large
instability. However, inhibition should increase with loss of
daytime heating. An isolated strong storm producing small hail
cannot be ruled out, but overall severe potential appears limited
given time of day and nebulous forcing for ascent.

...Central Texas...

Rounds of thunderstorms will continue overnight as lobes of
convectively enhanced vorticity maxima rotate around the mid/upper
low centered over west-central TX. Low-level warm advection will
persist through the night, maintaining rich boundary layer moisture, maintaining at least modest low-level instability. Vertically
veering low-level wind profiles will maintain 0-1 km SRH around
100-200 m2/s2, and a tornado or two will remain possible.

...AZ...

Strong thunderstorms could produce locally damaging/severe gusty
outflow winds through late evening. Reference MCD 1628 for
information on short term severe potential.

...MT/WY...

Severe probabilities have mostly be removed from WY and confined to
MT, where modest instability overlaps with strong effective shear
magnitudes. Isolated strong wind gusts remain possible through late
evening as convection shifts east toward a better low-level lapse
rate environment.

...WA/OR...

Scattered high-based showers and thunderstorms will persist tonight
across central OR into south-central WA. A belt of 30-40 kt
effective shear magnitudes may provide sufficient support within the
weakly unstable airmass for a couple of strong storms. Steep lapse
rates will favor strong outflow winds with this convection.

..Leitman.. 07/16/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Thu Jul 16 05:20:40 2026

ACUS01 KWNS 160520
SWODY1
SPC AC 160518

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1218 AM CDT Thu Jul 16 2026

Valid 161200Z - 171200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
WESTERN MONTANA...

...SUMMARY...
Severe thunderstorms will be possible across parts of western
Montana, mainly Thursday afternoon and evening. Locally damaging
winds may also occur across parts of New England, the Upper Midwest,
and the Mid-Atlantic.

...Northern Rockies...

An upper low will skim the Pacific Northwest coast as it lifts
northward through the period. Meanwhile, upper ridging will persist
across much of the Rockies to the Plains. Wedged between the upper
low and the western periphery of the upper ridging, a belt of
enhanced south/southwesterly deep-layer flow will overspread the
northern Rockies. Easterly low-level flow will transport 50s F
dewpoints across region beneath steep midlevel lapse rates. This
will support moderate destabilization (1000-2000 J/kg MLCAPE).
Scattered thunderstorms will develop during the afternoon.
Vertically veering wind profiles and increasing flow aloft will
result in 30+ kt effective shear magnitudes. Organized cells will
pose a risk for strong wind gusts and hail across much of the
region. The greatest risk for 1+ inch hail will be across portions
of western MT.

...New England...

A vigorous upper shortwave trough will move across the region
through evening. Strong west/northwest deep-layer flow is evident in
forecast soundings, with 40+ kt effective shear magnitudes likely.
Boundary layer moisture will be somewhat muted compared to the
previous few days, with dewpoints generally in the 50s F. Stronger
heating is expected to the north of the more prominent smoke plume
across southern New England, aiding in steepening low-level lapse
rates. While instability will remain modest, strong flow and steep
low-level lapse rates may support isolated strong/locally damaging
wind gusts as convection spreads southeast from Quebec and across
portions of northern New England through the afternoon.

...Southern PA/Mid-Atlantic vicinity...

Strong mid/upper-level flow will overspread the region on the
southern periphery of the upper shortwave trough moving across New
England. A surface front is expected to drop southward through the
day, approaching the PA/MD border vicinity by late afternoon. Rich
boundary layer moisture will be in place ahead of the surface front
and beneath steep midlevel lapse rates. This will foster a corridor
of 2000+ J/kg MLCAPE. Furthermore, forecast soundings show 30-40 kt
effective shear magnitudes and steep low-level lapse rates. This
environment generally should support organized cells/line segments.
However, convective coverage is uncertain given stronger forcing for
ascent focused north of the area. Additionally, it is uncertain if
smoke will continue to have a deleterious impact on an otherwise
favorable severe storm environment. Given conditional potential for
at least locally damaging gusts, have included low severe wind
probabilities.

...ND/MN...

A series of convectively enhanced vorticity maxima will migrate
across the Canadian Prairies atop the upper ridge and through
northwesterly flow aloft into parts of ND and northern MN this
afternoon into tonight. At the surface, a weak low and surface front
will move across ND into northern MN during the evening and
overnight hours. South/southeasterly low-level flow will maintain a moisture-rich boundary layer, supporting a corridor of modest
destabilization. Forecast soundings show supercell wind profiles,
but also increasing capping through the late afternoon/evening.
Nevertheless, most guidance develops convection across southern
Manitoba into northeast ND during the evening, spreading
east/southeast across northern MN during the nighttime hours. Some
risk for strong gusts and marginal hail appears possible,
necessitating low severe probabilities.

...AZ...

Thunderstorms are expected once again to develop over higher terrain
this afternoon/evening and spread westward across portions of
central/southern AZ. Deep layer flow will be weaker compared to
previous days, but modest instability and steep lapse rates amid
strong heating could support sporadic strong gusts.

..Leitman/Lyons.. 07/16/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Thu Jul 16 12:07:56 2026

ACUS01 KWNS 161207
SWODY1
SPC AC 161205

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0705 AM CDT Thu Jul 16 2026

Valid 161300Z - 171200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
WESTERN MONTANA AND NORTHERN NEW ENGLAND...

...SUMMARY...
Severe thunderstorms capable of producing large hail and gusty winds
will be possible across parts of the northern Rockies this afternoon
and evening. Isolated to scattered damaging winds may also occur
over portions of northern New England, the Upper Midwest, and
Mid-Atlantic. A brief tornado or two remains possible across a small
part of south-central Texas this morning.

...Northern Rockies...
A closed upper low will move slowly northward along the coast of
WA/OR through the period. Upper ridging will persist across much of
the Rockies to the Plains. Between these features, a belt of
modestly enhanced south/southwesterly deep-layer flow will
overspread the northern Rockies. Modest easterly low-level winds
will transport generally 50s to low 60s surface dewpoints across
this region beneath steep mid-level lapse rates. As daytime heating
occurs, moderate instability should develop. Scattered thunderstorms
are forecast to initially form over the higher terrain during the
afternoon. Veering wind profiles with height through mid/upper
levels and gradually strengthening flow aloft will support around
30-40 kt of effective bulk shear. Organized cells will pose a risk
for gusty winds and severe hail across much of the region. The
greatest risk for 1+ inch hail still appears to be across parts of
western MT.

...Northern New England...
A vigorous mid-level shortwave trough will move quickly
southeastward from southern Ontario/Quebec across New England
through the day. Strong west/northwest deep-layer flow is evident in
recent NAM/RAP forecast soundings. Boundary layer moisture will be
somewhat limited compared to prior days, with surface dewpoints
generally in the 50s. Still, somewhat greater daytime heating is
expected to the north of the more prominent smoke plume across
southern New England, which should help steepening low-level lapse
rates by late morning/early afternoon. While MLCAPE will remain
modest (around 250-500 J/kg), the strong low/mid-level westerly flow
and steepened low-level lapse rates should support scattered
damaging winds as low-topped convection spreads southeast from
Quebec and across portions of northern New England through the
afternoon. Confidence in this scenario occurring has increased
enough to add greater severe wind probabilities and a corresponding
Slight Risk to parts of northeast VT/northern NH and ME.

...Mid-Atlantic...
Enhanced west-northwesterly mid/upper-level winds will overspread
the Mid-Atlantic today on the southern periphery of the mid-level
shortwave trough moving across New England. A surface front is
expected to sag southward through the day, approaching the PA/MD
border vicinity by late afternoon. Rich low-level moisture will be
in place ahead of the surface front and beneath steepening mid-level
lapse rates spreading in from the OH Valley. This, along with
diurnal heating, will foster a corridor of moderate to locally
strong instability this afternoon. Furthermore, various NAM/RAP
forecast soundings show 30-40 kt of effective bulk shear and steep
low-level lapse rates present south of the front. This environment
would generally support organized cells/line segments. However,
overall thunderstorm coverage remains uncertain given that stronger
forcing for ascent should remain mostly north of the warm sector.
Additionally, it is uncertain if smoke will continue to have a
negative impact on an otherwise favorable environment for severe
thunderstorms. Given the conditional potential for at least locally
damaging winds, have maintained the Marginal Risk with minor
expansions.

...Northeast North Dakota/Northern Minnesota...
A series of convectively enhanced vorticity maxima will migrate
across the Canadian Prairies north of the prominent upper ridge over
the Plains/Rockies, and through northwesterly flow aloft into parts
of ND and northern MN this afternoon into tonight. At the surface, a
weak low and surface front will move across ND into northern MN
during the evening and overnight hours. South/southeasterly
low-level flow will maintain a moisture-rich boundary layer,
supporting a narrow corridor of instability. NAM/RAP forecast
soundings show supercell wind profiles, but also increasing capping
through the late afternoon/evening. Even so, most high-resolution
guidance develops convection across southern Manitoba into northern
ND during the evening, spreading east/southeast across northern MN
overnight. Isolated severe hail and damaging winds may occur with
this activity.

...South-Central Texas...
Low-level rotation has occasionally been noted with cells occurring
early this morning across parts of south-central TX in a very moist
and weakly unstable environment, aided by a 30-35 kt southerly
low-level jet. A brief tornado or two still appears possible with
this activity through the morning, as low-level shear will remain
sufficient for continued updraft rotation. With time, a gradual
weakening of the low-level jet and related shear should result in a
lessening risk for tornadoes. See Mesoscale Discussion 1631 for more
details on the near-term threat across this area.

...Arizona...
Thunderstorms will develop over the higher terrain of the Mogollon
Rim and southeast AZ this afternoon/evening, and subsequently spread
westward across portions of central/southern AZ. Mid-level winds are
expected to be weaker compared to previous days, but modest
instability and steep lapse rates amid strong heating could support
sporadic strong gusts.

..Gleason/Thornton.. 07/16/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Thu Jul 16 16:36:32 2026

ACUS01 KWNS 161636
SWODY1
SPC AC 161634

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1134 AM CDT Thu Jul 16 2026

Valid 161630Z - 171200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
WESTERN MONTANA AND NORTHERN NEW ENGLAND...

...SUMMARY...
Severe thunderstorms capable of producing large hail and gusty winds
will be possible across parts of the northern Rockies this afternoon
and evening. Isolated to scattered damaging winds may also occur
over portions of northern New England, the Upper Midwest, and
Mid-Atlantic. A brief tornado could occur across a small part of south-central/southwest Texas later today or tonight.

...Northern Rockies...
A closed upper low will move slowly northward along the coastal
Pacific Northwest through tonight. Upper ridging will persist across
much of the Rockies to the Plains. Between these features, a belt of
modestly enhanced south/southwesterly deep-layer flow will
overspread the northern Rockies. Modest easterly low-level winds
will transport generally 50s to low 60s F surface dewpoints across
this region beneath steep mid-level lapse rates. As daytime heating
occurs, moderate instability should develop. Scattered thunderstorms
are forecast to initially form over the higher terrain during the
afternoon. Veering wind profiles with height through mid/upper
levels and gradually strengthening flow aloft will support around
30-40 kt of effective bulk shear. Organized cells will pose a risk
for gusty winds and severe hail across much of the region. The
greatest risk for 1+ inch hail appears to be across parts of western
Montana.

...Northern New England...
A vigorous mid-level shortwave trough will move quickly
southeastward from southern Ontario/Quebec across New England today
with strong west/northwest deep-layer flow. Boundary layer moisture
will be somewhat limited compared to prior days, with surface
dewpoints generally in the 50s F. Still, somewhat greater daytime
heating is expected to the north of the more prominent smoke plume
across southern New England, which should help steepening low-level
lapse rates by late morning/early afternoon. While MLCAPE will
remain modest (around 250-500 J/kg), the strong low/mid-level
westerly flow and steepened low-level lapse rates should support
scattered damaging winds as low-topped convection spreads southeast
from Quebec and across portions of northern New England through the
afternoon near a secondary/weak front.

...Mid-Atlantic...
Enhanced west-northwesterly mid/upper-level winds will overspread
the Mid-Atlantic today on the southern periphery of the mid-level
shortwave trough moving across New England. A surface front is
expected to sag southward through the day, approaching the Pennsylvania/Maryland border vicinity by late afternoon. Rich
low-level moisture will be in place ahead of the surface front and
beneath steepening mid-level lapse rates spreading in from the Ohio
Valley. This, along with diurnal heating, will foster a corridor of
moderate to locally strong instability this afternoon. Furthermore,
various NAM/RAP forecast soundings show 30-40 kt of effective bulk
shear and steep low-level lapse rates present south of the front.
This environment would generally support organized cells/line
segments. However, overall thunderstorm coverage remains uncertain
given that stronger forcing for ascent should remain mostly north of
the warm sector. Additionally, it is uncertain to what extent that
smoke may continue to have a negative impact on an otherwise
favorable environment for severe thunderstorms.

...Northeast North Dakota/Northern Minnesota...
A series of convectively enhanced vorticity maxima will migrate
across the Canadian Prairies north of the prominent upper ridge over
the Plains/Rockies, and through northwesterly flow aloft into parts
of North Dakota and northern Minnesota this afternoon into tonight.
At the surface, a weak low and surface front will move across North
Dakota into northern Minnesota during the evening and overnight
hours. South/southeasterly low-level flow will maintain a
moisture-rich boundary layer, supporting a narrow corridor of
instability. NAM/RAP forecast soundings show supercell wind
profiles, but also increasing capping through the late
afternoon/evening. Even so, most high-resolution guidance develops
convection across southern Manitoba into northern North Dakota
during the evening, spreading east/southeast across northern
Minnesota overnight. Isolated severe hail and damaging winds may
occur with this activity, and a tornado risk cannot be ruled out.

...South-Central Texas...
While low-level shear/SRH has weakened since last night, and ongoing
convection remains extensive/repetitive, a northward drift of the
MCV and potential re-establishment of stronger low-level winds later
today into tonight could account for non-zero/brief tornado
potential.

...Arizona...
Thunderstorms will develop over the higher terrain of the Mogollon
Rim and southeast Arizona this afternoon/evening, and subsequently
spread westward across portions of central/southern Arizona. Modest
instability and steep lapse rates amid strong heating could support
sporadic strong gusts.

..Guyer/Squitieri.. 07/16/2026

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Thu Jul 16 19:54:02 2026

ACUS01 KWNS 161953
SWODY1
SPC AC 161951

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0251 PM CDT Thu Jul 16 2026

Valid 162000Z - 171200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
WESTERN MONTANA...

...SUMMARY...
Severe thunderstorms capable of producing large hail and gusty winds
will be possible across parts of the northern Rockies this afternoon
and evening. Isolated to scattered damaging winds may also occur
over portions of northern New England, the Upper Midwest, and
Mid-Atlantic. A brief tornado could occur across a small part of south-central/southwest Texas later today or tonight.

...20z Update...
The primary adjustment was to reduce wind probabilities across
portions of the Northeast behind a leading line of convection
attendant to a weak surface front. Falling temperatures and more
stable conditions in the wake of this front should preclude
additional thunderstorm development through the evening, though some
lingering threat persists across parts of New England as convection
continues to push east towards the Atlantic coast.

...Mid-Atlantic...
GOES visible imagery shows building cumulus across parts of
southeast PA within a favorable environment for organized
convection. Although guidance continues to suggest much of this
activity will mature along and off the coast, some potential for
severe wind, as well as large hail, is apparent based on latest RAP mesoanalyses and forecast guidance.

...North Dakota...
The 2% tornado risk probability line was expanded eastward along a
surface warm front evident in visible imagery and surface
observations. Warm and moist conditions and ambient low-level
vorticity along this boundary may support some potential for brief
tornadoes as thunderstorms begin to develop later this evening.

Elsewhere, the previous forecast remains on track. See the previous
discussion below for additional details.

..Moore.. 07/16/2026

.PREV DISCUSSION... /ISSUED 1134 AM CDT Thu Jul 16 2026/

...Northern Rockies...
A closed upper low will move slowly northward along the coastal
Pacific Northwest through tonight. Upper ridging will persist across
much of the Rockies to the Plains. Between these features, a belt of
modestly enhanced south/southwesterly deep-layer flow will
overspread the northern Rockies. Modest easterly low-level winds
will transport generally 50s to low 60s F surface dewpoints across
this region beneath steep mid-level lapse rates. As daytime heating
occurs, moderate instability should develop. Scattered thunderstorms
are forecast to initially form over the higher terrain during the
afternoon. Veering wind profiles with height through mid/upper
levels and gradually strengthening flow aloft will support around
30-40 kt of effective bulk shear. Organized cells will pose a risk
for gusty winds and severe hail across much of the region. The
greatest risk for 1+ inch hail appears to be across parts of western
Montana.

...Northern New England...
A vigorous mid-level shortwave trough will move quickly
southeastward from southern Ontario/Quebec across New England today
with strong west/northwest deep-layer flow. Boundary layer moisture
will be somewhat limited compared to prior days, with surface
dewpoints generally in the 50s F. Still, somewhat greater daytime
heating is expected to the north of the more prominent smoke plume
across southern New England, which should help steepening low-level
lapse rates by late morning/early afternoon. While MLCAPE will
remain modest (around 250-500 J/kg), the strong low/mid-level
westerly flow and steepened low-level lapse rates should support
scattered damaging winds as low-topped convection spreads southeast
from Quebec and across portions of northern New England through the
afternoon near a secondary/weak front.

...Mid-Atlantic...
Enhanced west-northwesterly mid/upper-level winds will overspread
the Mid-Atlantic today on the southern periphery of the mid-level
shortwave trough moving across New England. A surface front is
expected to sag southward through the day, approaching the Pennsylvania/Maryland border vicinity by late afternoon. Rich
low-level moisture will be in place ahead of the surface front and
beneath steepening mid-level lapse rates spreading in from the Ohio
Valley. This, along with diurnal heating, will foster a corridor of
moderate to locally strong instability this afternoon. Furthermore,
various NAM/RAP forecast soundings show 30-40 kt of effective bulk
shear and steep low-level lapse rates present south of the front.
This environment would generally support organized cells/line
segments. However, overall thunderstorm coverage remains uncertain
given that stronger forcing for ascent should remain mostly north of
the warm sector. Additionally, it is uncertain to what extent that
smoke may continue to have a negative impact on an otherwise
favorable environment for severe thunderstorms.

...Northeast North Dakota/Northern Minnesota...
A series of convectively enhanced vorticity maxima will migrate
across the Canadian Prairies north of the prominent upper ridge over
the Plains/Rockies, and through northwesterly flow aloft into parts
of North Dakota and northern Minnesota this afternoon into tonight.
At the surface, a weak low and surface front will move across North
Dakota into northern Minnesota during the evening and overnight
hours. South/southeasterly low-level flow will maintain a
moisture-rich boundary layer, supporting a narrow corridor of
instability. NAM/RAP forecast soundings show supercell wind
profiles, but also increasing capping through the late
afternoon/evening. Even so, most high-resolution guidance develops
convection across southern Manitoba into northern North Dakota
during the evening, spreading east/southeast across northern
Minnesota overnight. Isolated severe hail and damaging winds may
occur with this activity, and a tornado risk cannot be ruled out.

...South-Central Texas...
While low-level shear/SRH has weakened since last night, and ongoing
convection remains extensive/repetitive, a northward drift of the
MCV and potential re-establishment of stronger low-level winds later
today into tonight could account for non-zero/brief tornado
potential.

...Arizona...
Thunderstorms will develop over the higher terrain of the Mogollon
Rim and southeast Arizona this afternoon/evening, and subsequently
spread westward across portions of central/southern Arizona. Modest
instability and steep lapse rates amid strong heating could support
sporadic strong gusts.

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Fri Jul 17 01:01:00 2026

ACUS01 KWNS 170100
SWODY1
SPC AC 170059

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0759 PM CDT Thu Jul 16 2026

Valid 170100Z - 171200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF
WESTERN MONTANA AND EASTERN NORTH DAKOTA INTO WESTERN MINNESOTA...

...SUMMARY...
Severe thunderstorms capable of producing large hail and gusty winds
remain possible across parts of the northern Rockies this evening.
Severe storms with hail and a tornado or two are also expcted over
parts of the Upper Midwest into tonight.

...Northern Rockies...
Evening water vapor imagery showed a very large upper ridge centered
over the CONUS, with a broad plume of monsoon moisture east of an
upper low off the coast of the Olympic Peninsula. Numerous
thunderstorms are ongoing over the Intermountain West and northern
Rockies this evening and should persist for several more hours
tonight.

The strongest of these storms, including some supercells, should
persist over parts of the eastern ID panhandle and western MT this
evening. Here, moderate buoyancy and 40+ kt of effective shear will
continue to favor storm organization. Hail is likely, along with
some potential for severe gusts given steep lapse rates in the lower
and middle troposphere.

...Eastern into western MN...
At the crest of the expansive upper ride, several weak vorticity
maxima and jet streak were migrating along the Canadian/ND border.
An effective warm front/modified outflow boundary was observed from
near the international border into western MN. South of the front,
surface temperatures in the 90s and dewpoints in the lower to middle
70s F are supporting a very unstable air mass with MLCAPE of
4000-5000 J/kg. Veering wind profiles along and south of the warm
front will favor supercells or organized clusters this evening into
tonight as developing convection spreads southeastward toward the
Red River Valley. Despite only modest mid-level lapse rates, strong
to extreme buoyancy and 35-40 kt of deep-layer vertical shear will
support a risk for large hail (some 2+ in) with dominant supercells.
Backed low-level flow and enhanced ESRH along the cool side of the
boundary could support a tornado or two as well.

The primary focus for the severe storms will be along the warm front
where convergence is maximized, though isolated storms ongoing
farther southwest are possible with a localized threat for hail and
damaging winds in the more strongly mixed air mass. A Level 2 Slight
Risk has been introduced to cover the increase in severe risk
through this evening from eastern ND into western MN.

...Elsewhere...
Strong to severe storms have largely exited the eastern seaboard
this evening. Additional disorganized storms over the southeastern
US and southern Plains should linger into the overnight hours while
steadily weakening. Waning buoyancy and meager deep-layer vertical
shear should limit severe potential.

..Lyons.. 07/17/2026

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Fri Jul 17 06:00:12 2026

ACUS01 KWNS 170559
SWODY1
SPC AC 170558

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1258 AM CDT Fri Jul 17 2026

Valid 171200Z - 181200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF
THE NORTHERN ROCKIES...GREAT LAKES AND OHIO VALLEY TO THE SOUTHERN APPALACHIANS....

...SUMMARY...
Strong to potentially severe storms are possible today across parts
of western Montana and northern Idaho, and also across parts of the
Upper Midwest and northern Great Lakes. More isolated strong to
severe storms with damaging gusts are possible over parts of the
Ohio Valley and southern Appalachians.

...Northern Rockies and Adjacent Plains...
An upper low over the Pacific Northwest is forecast to lift slowly
northward as an expansive upper ridge continues to build across the
western US. East of the low, a broad area of monsoon moisture will
persist over much of the Rocky Mountains. Weak ascent on the
periphery of the upper low and diurnal heating across the higher
terrain should allow for scattered thunderstorm development through
the afternoon. While displaced from the core of the stronger flow
aloft as the upper low drifts to the north, sufficient effective
shear of 25-35 kt will exist for occasional storm organization.
Isolated hail and severe gusts could accompany the strongest storms
into the evening across ID and western MT.

...Upper Midwest and northern Great Lakes...
An upper trough initially over AB/SK will move southward into the
northern Great Lakes by early Saturday. A belt of stronger mid-level
flow accompanying the upper trough will aid in deepening a surface
low as it moves into western ON. A warm front will lift north with
the deepening low over the Upper Midwest. A cold front trailing the
surface low will provide a focus for thunderstorm development over
northern MN, WI and the UP of MI this afternoon and evening.

A cluster of elevated thunderstorms is likely to be ongoing early in
the period near or just across the international border. These
storms could reinvigorate with a risk for some damaging gusts and
hail, though confidence in the convective evolution is low. Later in
the day ahead of the cold front, moderate buoyancy and sufficient
deep-layer shear will conditionally support a threat for isolated
supercells or organized multicell clusters, with a threat of hail
and damaging winds. Any persistent supercell may also pose at least
a brief tornado threat, especially in closer proximity to the
surface low and warm front where low-level shear will be maximized.

As the main upper trough continues to southeast one or more clusters
of strong to severe storms may persist into the overnight along the
warm front. However, confidence in this scenario is lower owing to
the prior convection and uncertainties of diurnal development along
the cold front. Still, a strengthening wind field and ample moisture
could support a risk for damaging winds into northern Lower MI
overnight.

...OH Valley to the southern Appalachians...
A warm and seasonably moist air mass will support moderate to
locally strong buoyancy beneath the upper ridge from the OH valley
toward the Southeast and southern Appalachians. A weak, convectively
enhanced sub-tropical disturbance moving northward and the higher
terrain should focus more widespread diurnal thunderstorm activity
from portions of IN/OH, into eastern KY/TN, the western Carolinas
and northern GA. Despite weak deep-layer shear below 20 kt, moderate
to strong MLCAPE (2000-3000 J/kg) and PWATS exceeding 2 inches may
allow for sporadic damaging gusts with any stronger multicell
clusters.

...FL...
CAM guidance shows vigorous storm development just offshore of the
FL Gulf Coast Friday morning, in association with a weak midlevel
trough/low. Additional storm development is expected by afternoon
across much of the peninsula. Large buoyancy and high PWATs suggest
localized strong to severe gusts cannot be ruled out near the coast
and inland this afternoon.

..Lyons/Weinman.. 07/17/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Fri Jul 17 12:33:12 2026

ACUS01 KWNS 171232
SWODY1
SPC AC 171231

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0731 AM CDT Fri Jul 17 2026

Valid 171300Z - 181200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF
THE NORTHERN ROCKIES AND HIGH PLAINS...UPPER GREAT LAKES...AND OHIO
VALLEY INTO THE SOUTHEAST...

...SUMMARY...
Strong to potentially severe storms are possible today across parts
of western Montana and northern Idaho, and also across parts of the
Upper Midwest and northern Great Lakes. More isolated strong to
severe storms with damaging gusts are possible over parts of the
Ohio Valley into parts of the Southeast.

...Northern Rockies and adjacent High Plains...
To the east of an upper low near the WA/Vancouver vicinity, an upper
ridge with a plume of monsoonal moisture will extend northward from
the Great Basin into the northern Rockies and adjacent High Plains.
Orographic lift and heating will promote the development of
scattered thunderstorms this afternoon. Steepened low-level lapse
rates will potentially yield storms capable of isolated severe gusts
beginning this afternoon and continuing into the mid-late evening.
Isolated large hail may occur with the stronger thunderstorm cores,
especially over northwest MT where 0-6 km shear will be 25-35 kt.

...Upper Midwest and northern Great Lakes...
A cluster of weak thunderstorms over the MN Arrowhead will likely
move southeast this morning ahead of an amplifying upper trough
forecast to move from northern SK to the Upper Peninsula of MI
during the period. A cold front associated with the upper wave will
push southeastward across the Upper Midwest and provide a focus for thunderstorms later this afternoon and evening.

A warm frontal zone draped across the northern Great Lakes will
advance northeastward as a low over western ON moves eastward into
central ON by early evening. Forecast model guidance shows moderate
buoyancy developing today within a belt of 25-40 kt
west-northwesterly 500-mb flow. As a result, a few of the stronger thunderstorms will probably evolve into supercells and organized
multicell clusters. Isolated large hail and damaging gusts are the
primary hazards, although a brief tornado risk may also develop in
the areas surrounding Lake Superior. One or more clusters of strong
to severe storms may persist into the overnight along the warm
front. However, confidence in this scenario is lower owing to the
prior convection and uncertainties of diurnal development along the
cold front. Still, a strengthening wind field and ample moisture
could support a risk for damaging winds into northern Lower MI
overnight.

...OH Valley to the southern Appalachians and FL...
A moist and diurnally destabilizing airmass will support scattered
to numerous storms developing by the mid afternoon. Some of the
stronger water-loaded downdrafts will potentially be capable of
50-60 mph gusts and isolated wind damage.

...West-central TX...
A weak mid- to upper-level low over west TX will move little during
the day while a warm/moist conveyor persists across southern into
central parts of TX. An ongoing thunderstorm cluster will likely
continue across the Concho Valley aided in part by a convectively
augmented zone of low-level warm-air advection. Despite very moist
low levels and some enlargement of the low-level hodograph per KSJT
and KDFX VAD data, weak flow in the mid levels will likely promote
enough convective outflow to limit storm organization (i.e.,
transient storm-scale cyclonic shear) and favor a heavy rain threat.

..Smith.. 07/17/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Fri Jul 17 16:32:40 2026

ACUS01 KWNS 171632
SWODY1
SPC AC 171630

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1130 AM CDT Fri Jul 17 2026

Valid 171630Z - 181200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF
THE NORTHERN ROCKIES AND HIGH PLAINS...UPPER GREAT LAKES...AND OHIO
VALLEY TO THE SOUTHEAST...

...SUMMARY...
Strong to potentially severe storms are possible today across parts
of western Montana and northern Idaho, and also across parts of the
Upper Midwest and northern Great Lakes. More isolated strong to
severe storms with damaging wind gusts are possible over parts of
the Ohio Valley and Southeast.

...Northern Rockies and northern High Plains...
The region will be influenced by an increasingly progressive
shortwave trough moving northeastward from off the Washington coast
and over southern British Columbia. The preceding upper ridge will flatten/shift eastward particularly near the international border,
with a plume of rich monsoonal moisture extending into the region,
highlighted by prevalent middle 50s to lower 60s F dewpoints along
the Continental Divide. Orographic lift and heating will promote the development of scattered thunderstorms this afternoon, especially
across eastern/northern Idaho and western Montana. Steepened
low-level lapse rates will potentially yield storms capable of
isolated severe wind gusts beginning this afternoon and continuing
into mid-late evening. Isolated large hail may occur with the
stronger thunderstorm cores, especially over northwest Montana where
deep-layer shear may exceed 30 kt.

...Upper Midwest and northern Great Lakes...
A decaying cluster of storms continues to spread southeastward
across northern Michigan, and smoke will continue to be a factor
regionally, albeit with some west-to-east abatement later today. A
cold front associated with the upper wave will push southeastward
across the Upper Midwest and provide a focus for thunderstorm
redevelopment late this afternoon, and more so into this evening.
Forecast model guidance shows moderate buoyancy developing today
within a belt of 25-40 kt west-northwesterly 500-mb flow as upstream
shortwave trough amplification occurs.

A few of the stronger thunderstorms could evolve into supercells and
organized multicell clusters, although uncertainty persists
regarding the overall magnitude/extent of today's severe potential.
Isolated large hail and damaging gusts are the primary hazards,
although a brief tornado risk may also develop in the areas
surrounding Lake Superior. One or more clusters of strong to severe
storms may persist into the overnight along the warm front.

...Ohio Valley to the southern Appalachians and Florida...
A moist and diurnally destabilizing airmass will support scattered
to numerous storms developing by the mid afternoon. Some of the
stronger water-loaded downdrafts will potentially be capable of
50-60 mph gusts and isolated wind damage.

...West-central Texas...
A weak mid- to upper-level low over west Texas will move little
during the day while a warm/moist conveyor persists across southern
into central parts of Texas. Despite very moist low levels and some
enlargement of the low-level hodograph, weak flow in the mid levels
should limit storm organization and meaningful supercell potential,
more so favoring a heavy rain threat.

..Guyer/Thompson.. 07/17/2026

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Fri Jul 17 19:53:12 2026

ACUS01 KWNS 171952
SWODY1
SPC AC 171951

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0251 PM CDT Fri Jul 17 2026

Valid 172000Z - 181200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM CENTRAL
IDAHO INTO MONTANA...THE GREAT LAKES...AND THE OHIO VALLEY INTO THE SOUTHEAST...

...SUMMARY...
Strong to potentially severe storms are possible today across parts
of western Montana and northern Idaho, and also across parts of the
Upper Midwest and northern Great Lakes. More isolated strong to
severe storms with damaging wind gusts are possible over parts of
the Ohio Valley and Southeast.

...20z Update...
The previous forecast remains largely on track based on latest
trends in ensemble guidance. Recent runs of the RRFS/HRRR
time-lagged ensemble continue to show some potential for organized
convection across northern WI and into the U.P. of Michigan later
this evening, and latest trends in GOES imagery show building
cumulus that seem to support these solutions. However, the overall
ensemble signal for widespread severe convection on the U.S. side of
the international border remains limited. Similarly, a corridor of
more focused wind potential may emerge across west-central MT this
evening, but given low ensemble probabilities for severe winds,
coupled with modest low-level lapse rates in latest RAP mesoanalyses
and forecast soundings, limits confidence in a widespread severe
wind threat. See the previous discussion below and MCD #1641 for
additional details.

..Moore.. 07/17/2026

.PREV DISCUSSION... /ISSUED 1130 AM CDT Fri Jul 17 2026/

...Northern Rockies and northern High Plains...
The region will be influenced by an increasingly progressive
shortwave trough moving northeastward from off the Washington coast
and over southern British Columbia. The preceding upper ridge will flatten/shift eastward particularly near the international border,
with a plume of rich monsoonal moisture extending into the region,
highlighted by prevalent middle 50s to lower 60s F dewpoints along
the Continental Divide. Orographic lift and heating will promote the development of scattered thunderstorms this afternoon, especially
across eastern/northern Idaho and western Montana. Steepened
low-level lapse rates will potentially yield storms capable of
isolated severe wind gusts beginning this afternoon and continuing
into mid-late evening. Isolated large hail may occur with the
stronger thunderstorm cores, especially over northwest Montana where
deep-layer shear may exceed 30 kt.

...Upper Midwest and northern Great Lakes...
A decaying cluster of storms continues to spread southeastward
across northern Michigan, and smoke will continue to be a factor
regionally, albeit with some west-to-east abatement later today. A
cold front associated with the upper wave will push southeastward
across the Upper Midwest and provide a focus for thunderstorm
redevelopment late this afternoon, and more so into this evening.
Forecast model guidance shows moderate buoyancy developing today
within a belt of 25-40 kt west-northwesterly 500-mb flow as upstream
shortwave trough amplification occurs.

A few of the stronger thunderstorms could evolve into supercells and
organized multicell clusters, although uncertainty persists
regarding the overall magnitude/extent of today's severe potential.
Isolated large hail and damaging gusts are the primary hazards,
although a brief tornado risk may also develop in the areas
surrounding Lake Superior. One or more clusters of strong to severe
storms may persist into the overnight along the warm front.

...Ohio Valley to the southern Appalachians and Florida...
A moist and diurnally destabilizing airmass will support scattered
to numerous storms developing by the mid afternoon. Some of the
stronger water-loaded downdrafts will potentially be capable of
50-60 mph gusts and isolated wind damage.

...West-central Texas...
A weak mid- to upper-level low over west Texas will move little
during the day while a warm/moist conveyor persists across southern
into central parts of Texas. Despite very moist low levels and some
enlargement of the low-level hodograph, weak flow in the mid levels
should limit storm organization and meaningful supercell potential,
more so favoring a heavy rain threat.

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Sat Jul 18 01:02:44 2026

ACUS01 KWNS 180102
SWODY1
SPC AC 180100

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0800 PM CDT Fri Jul 17 2026

Valid 180100Z - 181200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
IDAHO AND MONTANA...HE UPPER MIDWEST...AND PORTIONS OF THE
SOUTHEAST...

...SUMMARY...
Strong to potentially severe storms remain possible this evening and
tonight across parts of the Upper Midwest and northern Great Lakes
and western Montana/northern Idaho. Sporadic strong to severe storms
with damaging wind gusts cannot be ruled out over parts of the
Southeast.

...Upper Midwest and Great Lakes...
Early evening water vapor imagery showed an upper trough and belt of
enhanced mid-level flow moving from southern Canada into the
northern Great Lakes. Ahead of the trough, a prominent warm front is
in place along the southern edge of Lake Superior, into the UP of
MI. Along the front, an associated surface cyclone was observed over
Lake Superior with a cold front trailing southwestward into eastern
MN and northwest WI.

Several strong to severe storms have developed and intensified
across far eastern MN, northern WI and the shelf waters of Lake
Superior this evening ahead of the cold front. High-res model
guidance and convective trends suggest these storms should generally
spread southeastward across northern WI this evening. Here in the
warm sector, mid to upper 80s F surface temperatures and seasonably
high dewpoints in the 60s and 70-s F are supporting a moderate to
strongly unstable air mass, more than sufficient for maintenance of
the ongoing severe storms. 40-50 kt of deep-layer shear are also
supporting organized clusters and some supercell structures. This
suggests hail and damaging winds are possible into early tonight.

Across the UP, convection has been slower to evolve owing to
lingering inhibition and weaker buoyancy. However, model guidance
and recent radar trends show a gradual increase in storm coverage
this evening. If some clustering can occur, a brief tornado risk may
also develop given enhanced low-level shear along the warm front and
near the lakes. An isolated risk for damaging winds could also
continue overnight across the UP and far northern Lower MI with any longer-lived clusters along the front.

...ID and MT...
On the northern fringes of an expansive upper ridge, an upper low
over the Pacific Northwest was supporting a broad fetch of
seasonably high monsoon moisture and moderate destabilization.
Scattered thunderstorms are ongoing over parts of ID and MT this
evening and should continue into the early overnight period. While
displaced from stronger westerly flow aloft, effective shear near
25-30 kt could support a few organized storms with a risk for hail
and damaging winds over parts of ID and MT. Especially if any
clustering can occur.

...OH valley to the Southern Appalachians and Southeast...
Numerous storms ongoing this evening should slowly diminish in
coverage and intensity over the next couple of hours as the
boundary-layer stabilizes. The highest concentration of stronger
storms should remain across parts of the Southeast in FL and GA
where a larger reservoir of moderate to large buoyancy remains. An
isolated damaging gust will remain possible with the more persistent thunderstorm clusters this evening. However, the weakening buoyancy
and increasing stabilization should gradually limit the damaging
wind risk into tonight.

..Lyons.. 07/18/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Sat Jul 18 05:59:14 2026

ACUS01 KWNS 180559
SWODY1
SPC AC 180557

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1257 AM CDT Sat Jul 18 2026

Valid 181200Z - 191200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS OVER PORTIONS
OF THE NORTHEAST...MID ATLANTIC AND LOWER GREAT LAKES....

...SUMMARY...
Severe thunderstorms are expected across portions of the Ohio Valley
and Lower Great Lakes into the Mid-Atlantic and Northeast, this
afternoon into the evening. Some threat may linger into late
tonight.

...OH valley and Great Lakes to the Mid Atlantic and Northeast...
An unseasonably strong upper trough is forecast to move from
southern ON into the northeast US through early Sunday. As the
trough intensifies, a 60+ kt mid-level jet will overspread portions
of eastern Canada and the Northeast, aiding in deepening a surface
low across the eastern St Lawrence Valley. Strong surface mass
response will lift a warm front northward across eastern NY and
southern New England. South of the boundary, a very moist air mass
will be in place ahead of a cold front over the OH Valley and Great
Lakes. A rather broad area, is expected to be conducive for numerous
strong to severe storms with the potential for widespread damaging
winds over the Northeastern US today and tonight.

One or more clusters of showers/thunderstorms appears likely to be
ongoing at the start of the period from central PA and southern NY
into eastern ON as isentropic ascent increases along the advancing
warm front. The impact of this overnight/early morning convection is
somewhat uncertain, but most guidance shows substantial air mass
recovery in its wake by midday with dewpoints in the mid 70s across
much of the Mid Atlantic. Given the degree of moisture and minimal
inhibition present, even modest diurnal heating should support rapid destabilization with MLCAPE of 2000-3000 J/kg common by early
afternoon.

Several different forcing regimes are expected to be active which
makes the convective evolution highly uncertain. The early morning
storms near the advancing warm front in PA could re-intensify as the
air mass to their south and east gradually destabilizes. This would
favor an increasing risk for damaging gusts. 35-45 kt of deep-layer
shear could also support some supercell structures. A couple of
tornadoes (some possibly strong) may occur, given favorable backed
low-level flow and ESRH of 200-300 m2/s2 near the front from
southeastern PA, into NJ and southern NY.

Additional storms are likely to develop along a pre-frontal
confluence axis/lee trough east of the higher terrain from southern
PA into eastern MD and northern VA to northern NC. Large buoyancy
and deep-layer shear of 30-40 kt would favor a mixed mode of line
segments and supercells. These storms should move eastward toward
DelMarVa and the I-95 Corridor by early afternoon. RAP/HRRR
soundings show 40-50 kt of flow aloft as the upper trough and jet
streak move overhead. Regardless of storm mode, the high PWAT
content (2-2.5 inches) should foster strong downdrafts and momentum
transfer to the surface. Widespread damaging gusts are likely from
northeast VA, eastern MD, into southeast PA and NJ. Higher wind
probabilities (60%) may be needed if confidence in a more
linear/cluster storm mode develops.

To the west, ahead of the cold front, a broken band of cells and
clusters is likely from NY/VT to the Lower Great Lakes. The
strongest vertical shear should reside across upstate NY into
northwest PA and northeast OH, where a few supercells are possible.
While farther west, strongly veered surface flow should result in
more linear storm modes. Multiple wind-damage swaths may accompany
these storms, along with some potential for isolated hail. 70s F
surface dewpoints and enhanced low-level SRH could also support a
tornado threat with any discrete or embedded supercells, especially
closer to the surface low and near the effective warm frontal zone
where low-level shear is more favorable.

...Northern Rockies...
The mid/upper-level low that has lingered over the Pacific Northwest
this week is forecast to move northeastward and weaken to an open
wave as it lifts across far northern ID/MT into southern Canada.
While only glancing over the northern Rockies, modestly enhanced
southwesterly flow aloft will be maintained across the region
through the day/evening. Monsoon moisture and strong diurnal heating
will support widely scattered storm development during the
afternoon, with MLCAPE increasing to near 1000 J/kg and effective
shear of 30+ kt. This could support a threat of isolated hail and
localized strong to severe gusts with the more robust storms.

...Gulf Coast...
A remnant MCV may serve as a focus for diurnal thunderstorm
development along the northern Gulf Coast today. While vertical
shear is limited, locally moderate to strong buoyancy and very high
PWAT values could support sporadic downbursts with damaging gusts.
However, confidence in how widespread or sustained the severe threat
is too low for wind probabilities.

..Lyons/Weinman.. 07/18/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Sat Jul 18 12:21:16 2026

ACUS01 KWNS 181221
SWODY1
SPC AC 181219

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0719 AM CDT Sat Jul 18 2026

Valid 181300Z - 191200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS OVER PORTIONS
OF THE NORTHEAST...MID ATLANTIC AND LOWER GREAT LAKES...

...SUMMARY...
Severe thunderstorms are expected across portions of the Ohio Valley
and Lower Great Lakes into the Mid-Atlantic and Northeast this
afternoon and evening. Damaging gusts will be the primary threat,
but a few tornadoes are possible, including perhaps a strong
tornado.

...OH Valley and Great Lakes to the Mid Atlantic and Northeast...
Water-vapor imagery this morning shows a potent mid-level shortwave
trough moving southeast over the Upper Great Lakes towards the
Northeast during the period. The primary upper vorticity max will
rotate through the base of the larger-scale trough and through the
St. Lawrence Valley, before an upstream disturbance west of James
Bay this morning pivots southeast and reaches Maine/eastern Quebec
by early Sunday. Surface analysis this morning places a 1004-mb low
north of Georgian Bay and a cold front extending west-southwestward
into northern IA. An attendant warm front arching southeastward
through the Lower Great Lakes and draped over the Mid-Atlantic
states will advance northward as the cyclone develops east towards
northern Maine by late evening. Concurrently, the cold front will
push southeast across much of Great Lakes into the OH Valley.

South of the boundary, a very moist air mass was sampled this
morning by 12 UTC raobs and surface observations (i.e., upper 60s to
lower 70s F dewpoints). A few thunderstorm clusters this morning
have developed near the warm frontal zone from the Lower Great Lakes
into the Mid-Atlantic states. The early day storm activity will
likely be limited in storm vigor, due in part to initially
widespread cloud cover inhibiting strong heating in the areas
downstream over parts of PA/NY. Gradual dissipation of clouds and
heating coupled with the northeastward advancement of the warm
sector will promote a broad area to become moderately to strongly
unstable later today (1000-3000 J/kg MLCAPE) from the OH Valley
eastward into the Mid-Atlantic and parts of the Northeast.

A belt of westerly 30-45 kt 700-mb flow from northern VA into the
Northeast will aid in storm organization and severe potential this
afternoon and evening. Models differ substantially regarding
evolution/timing of possible bands of storms and clusters with
embedded cells. Regardless of specific details, it seems plausible
several multicellular bands of storms will develop during peak
heating and organize as these bands move east. Some of the more
intense cells will potentially become supercellular posing an
all-hazards severe risk. Have largely unchanged the previous
outlook given the inherent thunderstorm evolution-based
uncertainties. Potentially widespread damaging gusts [50-60 mph,
locally stronger (55-70 mph) perhaps paralleling the I-95 corridor
from Chesapeake Bay into southern New England]. A few tornadoes are
possible both from linear and cellular storm structures given some
low-level hodograph enlargement and moist low levels.

Farther west, veered low-level flow ahead of the cold front will
promote upscale growth into a few bands of cells and line segments
across the southern Great Lakes into the OH Valley. Damaging gusts
appear to be the primary hazard but a localized risk for hail and
perhaps a couple of tornadoes may accompany this activity.

...Northern Rockies...
The mid/upper-level low that has lingered over the Pacific Northwest
this week is forecast to move northeastward and weaken to an open
wave as it lifts across far northern ID/MT into southern Canada.
While only glancing over the northern Rockies, modestly enhanced
southwesterly flow aloft will be maintained across the region
through the day/evening. Monsoon moisture and strong diurnal
heating will support widely scattered storm development during the
afternoon, with MLCAPE increasing to near 1000 J/kg and effective
shear of 30+ kt. This could support a threat of isolated hail and
localized strong to severe gusts with the more robust storms.

..Smith/Broyles.. 07/18/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Sat Jul 18 16:22:18 2026

ACUS01 KWNS 181622
SWODY1
SPC AC 181620

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1120 AM CDT Sat Jul 18 2026

Valid 181630Z - 191200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON
THROUGH LATE EVENING FROM THE LOWER GREAT LAKES INTO THE
MID-ATLANTIC...

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS LATE THIS
AFTERNOON EVENING FOR PARTS OF WESTERN MONTANA...

...SUMMARY...
Severe thunderstorms are expected across portions of the Ohio Valley
and Lower Great Lakes into the Mid-Atlantic and Northeast this
afternoon and evening. Damaging gusts will be the primary threat,
but a few tornadoes are possible, including perhaps a strong
tornado.

...Mid-Atlantic to the lower Great Lakes this afternoon/evening...
Ongoing convection across central PA/NY will continue to spread
eastward through early afternoon within a warm advection zone along
and north of a surface warm front. The warm front will move
northward today in advance of a surface cyclone and associated
midlevel trough now in the vicinity of Lake Huron. In the wake of
the ongoing convection, destabilization will occur as boundary-layer
dewpoints rise to near 70 F and surface temperatures into the 80s,
resulting in moderate buoyancy in the warm sector. Destabilization
will occur earlier immediately south-through-west of the ongoing
storms across eastern PA/NJ, and a little later this afternoon into
central NY.

Additional thunderstorm development is beginning in southwest PA and
vicinity as of 16z and a continued increase in storms is expected
into early-mid afternoon along a cold front and along pre-frontal
confluence zones/lake-enhanced boundaries. A mixed convective mode
(line segments and clusters) is expected, with embedded bowing
segments and a chance for pre-frontal supercells in PA/NY/NJ where
vertical shear and hodograph curvature will be larger along the warm
front. Wind damage will be the primary severe threat with both the
frontal convection and pre-frontal storms, with a few tornadoes
possible with supercell structures and/or embedded mesovortices.

...Northern Rockies late this afternoon/evening...
Scattered thunderstorm development is expected later this
afternoon/evening across western MT and vicinity, within the
northwest fringe of the midlevel ridge and monsoonal moisture plume.
Midlevel flow will be somewhat enhanced to the immediate southeast
of a midlevel trough moving over southeast BC, thus some organized
storm structures will be possible with faster storm motions compared
to yesterday. Occasional severe outflow gusts and large hail up to
1.5 inches in diameter will be the main threats.

..Thompson/Bunting.. 07/18/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Sat Jul 18 19:52:52 2026

ACUS01 KWNS 181952
SWODY1
SPC AC 181951

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0251 PM CDT Sat Jul 18 2026

Valid 182000Z - 191200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS THE
LOWER GREAT LAKES AND MID-ATLANTIC...

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS PORTIONS OF
WESTERN TO CENTRAL MONTANA...

...SUMMARY...
Severe thunderstorms are expected across portions of the Ohio Valley
and Lower Great Lakes into the Mid-Atlantic and Northeast this
afternoon and evening. Damaging gusts will be the primary threat,
but a few tornadoes are possible, including perhaps a strong
tornado.

...20z Update...
The previous forecast remains on track with only minor adjustments
required based on recent convective trends. Lingering clouds and
stratiform precipitation across northern NY and into VT/NH continues
to limit confidence in the degree of destabilization that will occur
through the remainder of the day. Latest high-res ensemble guidance
has captured recent trends and depicts limited potential for intense
convection through this evening. Severe wind/hail probabilities have
been reduced to reflect the decreasing potential. For additional
short-term forecast details across the lower Great Lakes see MCD
#1650.

Further west, the 5/15% wind probabilities have been expanded
slightly eastward to account for trends in recent guidance that
depict some threat for severe winds across central MT later tonight
as thunderstorms begin to cluster. Given building buoyancy, strong
shear across the region (per recent mesoanalysis estimates), and
building cumulus within the terrain, environmental trends appear to
support the eastward expansion. See MCD #1651 for additional
short-term details.

..Moore.. 07/18/2026

.PREV DISCUSSION... /ISSUED 1120 AM CDT Sat Jul 18 2026/

...Mid-Atlantic to the lower Great Lakes this afternoon/evening...
Ongoing convection across central PA/NY will continue to spread
eastward through early afternoon within a warm advection zone along
and north of a surface warm front. The warm front will move
northward today in advance of a surface cyclone and associated
midlevel trough now in the vicinity of Lake Huron. In the wake of
the ongoing convection, destabilization will occur as boundary-layer
dewpoints rise to near 70 F and surface temperatures into the 80s,
resulting in moderate buoyancy in the warm sector. Destabilization
will occur earlier immediately south-through-west of the ongoing
storms across eastern PA/NJ, and a little later this afternoon into
central NY.

Additional thunderstorm development is beginning in southwest PA and
vicinity as of 16z and a continued increase in storms is expected
into early-mid afternoon along a cold front and along pre-frontal
confluence zones/lake-enhanced boundaries. A mixed convective mode
(line segments and clusters) is expected, with embedded bowing
segments and a chance for pre-frontal supercells in PA/NY/NJ where
vertical shear and hodograph curvature will be larger along the warm
front. Wind damage will be the primary severe threat with both the
frontal convection and pre-frontal storms, with a few tornadoes
possible with supercell structures and/or embedded mesovortices.

...Northern Rockies late this afternoon/evening...
Scattered thunderstorm development is expected later this
afternoon/evening across western MT and vicinity, within the
northwest fringe of the midlevel ridge and monsoonal moisture plume.
Midlevel flow will be somewhat enhanced to the immediate southeast
of a midlevel trough moving over southeast BC, thus some organized
storm structures will be possible with faster storm motions compared
to yesterday. Occasional severe outflow gusts and large hail up to
1.5 inches in diameter will be the main threats.

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Sun Jul 19 01:02:26 2026

ACUS01 KWNS 190102
SWODY1
SPC AC 190100

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0800 PM CDT Sat Jul 18 2026

Valid 190100Z - 191200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS CENTRAL
PENNSYLVANIA AND ACROSS PORTIONS OF WESTERN MONTANA...

...SUMMARY...
Storms capable of wind damage may continue for another hour or so
across central Pennsylvania before dissipating. Additional
strong-to-severe thunderstorms capable of damaging winds and hail
will be likely across portions western Montana

... 01Z Update ...

Overall thunderstorm intensity continues to wane across much of the
northeast with the loss of daytime heating and multiple rounds of
thunderstorms acting to stabilize the airmass. However, a few
damaging thunderstorm wind gusts will be possible from far eastern
Ohio into southern New England for perhaps another hour or two. The
most likely area for wind damage is across central Pennsylvania
where the most intense thunderstorms are currently found. These
storms should weaken further in the next couple of hours, bringing
an end to the organized severe threat.

Across western Montana, sufficient buoyancy is in place to support
ongoing convection, some of which has produced severe wind gusts
this afternoon. Steep lapse rates coupled with gradually
strengthening mid-level flow will support an ongoing severe threat,
including a couple of outflow-driven convective clusters. Please see
MCD #1656 for more details.

..Marsh.. 07/19/2026

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Sun Jul 19 06:02:58 2026

ACUS01 KWNS 190602
SWODY1
SPC AC 190600

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0100 AM CDT Sun Jul 19 2026

Valid 191200Z - 201200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM NORTH GEORGIA
INTO SOUTHERN VIRGINIA AND ACROSS THE DAKOTAS INTO WESTERN
MINNESOTA...

...SUMMARY...
Severe thunderstorms capable of damaging winds will be possible from
parts of north Georgia, across the Carolinas, and into southern
Virginia this afternoon. Additional severe thunderstorms capable of
damaging winds and large hail will be possible this afternoon and
evening across parts of the Dakotas and western Minnesota.

... Synopsis ...

The base-state mid-level pattern today will feature a western US
ridge and eastern US trough, with a weak closed low over the
northeast Gulf. Within this background flow field, a short-wave
trough will be exiting the Northeast US and a closed low across the
Canadian Prairies will crest the western ridge before digging
southeast late in the day toward the Upper Midwest.

At the surface, a large anticyclone will settle into the Great Lakes
region during the day. On the periphery of this anticyclone, a cold
front will be draped from coastal Virginia to the west-southwest,
before arcing northwest into the Mid-Mississippi Valley and then
into the Upper Midwest. This front will sag south across the eastern
US, while beginning to lift north and east across the Mississippi
Valley and Upper-Midwest. The front will act to delineate a very
warm/hot and moist airmass to the south and west from a cooler/dryer
airmass to the north and east.

... Georgia into southern Virginia and the greater Southeast ...

To the south of the advancing surface front, temperatures will warm
into the low-to-mid-90Fs from northern Georgia into southern
Virginia. At the same time, surface dewpoints of the upper-60Fs and
low-70Fs will be maintained. The result will be an strongly unstable environment with HREF ensemble mean MUCAPE between 1500-2000 J/kg
across the region. Forecast soundings show precipitable water
greater than 1.75 inches across much of the area, with a band of
precipitable water in excess of 2 inches. This, coupled with steep
sub-cloud layer lapse rates (approaching 8 C/km) which will support
wind damage potential with any sustained thunderstorm updraft.

Surrounding this area, more scattered thunderstorm development is
expected within the moist and unstable environment. At this time, it
appears a corridor of higher likelihood for thunderstorm development
will extend from southeast Louisiana northeast toward northern
Georgia. This increased thunderstorm activity appears to be
associated with a band of modest convergence in the 850-700 millibar
layer to the north of a weak low across the northeast Gulf. Damaging
wind gusts will be possible with some of these storms.

Another potential area of damaging wind gusts will be across
north-central Florida into far south-central Georgia. Here, HREF
guidance shows an east-northeast expanding band of thunderstorms
emanating from the low over the northeast Gulf.

... Dakotas into western Montana ...

Temperatures are expected to warm into the upper-90Fs to the
low-100Fs during the afternoon to the east of a low-level trough
axis developing in the lee of the Rockies in the northern High
Plains. To the east of this trough axis, HREF ensemble mean
dewpoints in the mid-to-upper-60Fs will combine with those hot
afternoon temperatures to support a very unstable environment, with
HREF ensemble mean MUCAPE values between 1500-2000 J/kg across the
Dakotas and individual members considerably higher (3000-4000 J/kg).

Scattered thunderstorms are expected to develop across the Dakotas
by mid afternoon as convective temperatures are approached and
modest height falls overspread the area. Long, straight hodographs
and effective-layer shear around 40-knots will support supercellular structures, including storm splits, early in the thunderstorm
convective life cycle. Large hail, potentially in excess of 2
inches, will be possible with these initial storms. However, dry
sub-cloud layers and low-level lapse rates around 9 C/km will
support strong convective outflows that will tend to favor upscale
growth, especially in regions where storm splits interact with one
another. One or more convective clusters will move east-southeast
during the late afternoon and evening continuing the threat for
damaging winds, before eventually weakening overnight.

..Marsh/Weinman.. 07/19/2026

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Sun Jul 19 12:48:24 2026

ACUS01 KWNS 191248
SWODY1
SPC AC 191246

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0746 AM CDT Sun Jul 19 2026

Valid 191300Z - 201200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM NORTH GEORGIA
INTO SOUTHERN VIRGINIA AND ACROSS THE DAKOTAS INTO WESTERN
MINNESOTA...

...SUMMARY...
Scattered damaging wind gusts are possible this afternoon over
portions of the Southeast. Scattered severe thunderstorms capable
of severe wind gusts and large hail are possible late this afternoon
through the evening across parts of the Upper Midwest.

... Southeast ...
Water-vapor imagery this morning shows a mid-level trough over the
Gulf of St. Lawrence and the Northeast U.S. moving east towards the
western Atlantic. A seasonably strong cold front over the OH Valley
eastward into the northern Mid-Atlantic states, will push south
before weakening over VA. A very moist airmass evident in 12 UTC
area raobs (14-15 g/kg lowest 100-mb mean mixing ratios) will
heat/destabilize across VA into the southern Appalachians.
Scattered thunderstorms will likely develop by midday into the early
afternoon both over the higher terrain and near the front. Slightly
stronger westerly flow over VA into the northern half of NC will
favor eastward-moving clusters this afternoon. High PW and
steepened low-level lapse rates will likely favor water-loading
within the stronger downdrafts. Scattered 50-60 mph gusts capable
of wind damage will be the primary hazard. Farther southwest over
GA into AL, a couple of bands of storms may yield wind-damage
potential with the stronger downdrafts. Isolated severe gusts are
also possible across parts of the central FL Peninsula northward
into southern GA.

...Upper Midwest...
A mid-level anticyclone will remain centered over the central
Rockies as an upper speed max intensifies and overspreads MT
eastward into MN. An associated mid-level trough initially over
Alberta will pivot east-southeast into Manitoba and adjacent
portions of ND-MN. Southerly low-level flow will advect richer
moisture northward into the Dakotas/MN region during the day.
Models show a relatively narrow tongue of 60s to near 70 F dewpoints
to the east of lee trough. In between a southeastward-moving cool
front and the lee trough, deep boundary layer mixing is expected.
Models generally show 1500-3000 J/kg MLCAPE over the Dakotas by mid
afternoon beneath 70 to 90-kt westerly 200-mb flow. Widely
scattered thunderstorms are expected to develop across the Dakotas
by mid to late afternoon as convective inhibition erodes.
Elongated, straight hodographs and effective shear around 40 kt will
support an initial supercell mode. Very large hail (1 to 3.5 inches
in diameter) is possible with a few of these supercells. As
additional storms develop towards the early evening, convective
outflow and additional storm mergers may lead to upscale growth of a severe-wind producing linear cluster (most probable over the eastern
ND into adjacent SD-MN). Peak gusts with this activity are forecast
in the 60-85 mph range. These storms will move east into parts of
the eastern Dakotas and western MN before eventually weakening
overnight.

..Smith/Broyles.. 07/19/2026

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Sun Jul 19 16:25:56 2026

ACUS01 KWNS 191625
SWODY1
SPC AC 191624

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1124 AM CDT Sun Jul 19 2026

Valid 191630Z - 201200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS
AFTERNOON/EVENING ACROSS PARTS TO THE SOUTHEAST AND THROUGH TONIGHT
ACROSS THE DAKOTAS AND MINNESOTA...

...SUMMARY...
Scattered damaging wind gusts are possible this afternoon over
portions of the Southeast. Scattered severe thunderstorms capable
of severe wind gusts and large hail are possible late this afternoon
through tonight from the Dakotas into Minnesota.

...Dakotas/MN this afternoon into tonight...
A midlevel trough over southern SK will suppress the northern extent
of the ridge over the Great Plains as an associated surface
trough/front moves into ND this afternoon. Strong surface
heating/mixing and weak ascent along the wind shift could support
thunderstorm development after about 22z beginning in south central
ND and expanding into northern SD and northeast ND through late
evening. The initial storms will be relatively high based with
forecast hodographs favoring splitting supercells capable of
producing significant outflow gusts (80+ mph) and isolated very
large hail (2-3+ inch diameter). Storms are expected to evolve into
a cluster or two tonight while spreading east-southeastward toward
western MN with a continued threat for occasional severe outflow
gusts and large hail.

...Carolinas and vicinity this afternoon/evening...
A weak cold front will continue to drift southward across VA/KY
toward NC through the afternoon, in association with the southern
periphery of a midlevel trough moving over the Mid-Atlantic and
southern New England. The southern extent of ~30 kt midlevel flow
overlaps the baroclinic zone and northern extent of the unstable
warm sector. Though midlevel lapse rates are not steep per 12z
soundings, surface temperatures warming into the 90-95 F range with
dewpoints in the low-mid 70s will drive MLCAPE of 2500-3500 J/kg
with negligible convective inhibition and steepening low-level lapse
rates. Scattered thunderstorm development is likely by early-mid
afternoon along the differential heating zone near the cold front,
as well as along a subtle surface trough across eastern NC.
Multicell clusters are the primary expected storm mode with the
potential to produce occasional wind damage with downbursts this afternoon/evening. Vertical shear will be a little stronger across
southeast VA/northeast NC where some storm organization will be
possible.

...Tropical Depression 2 in the eastern Gulf...
NHC has initiated advisories on Tropical Depression 2 in the eastern
Gulf, centered roughly 130 n mi west of Tampa as of 15z. Though
some outer eastern bands will affect the FL Gulf coast this
afternoon, it appears that enhancements to flow/shear are too
marginal to support any substantial threat of outer band
supercells/tornadoes along the FL Gulf coast through tonight.
Still, isolated strong outflow gusts will be possible with broken
thunderstorm bands this afternoon/evening across central/north FL
and south GA.

...AL area this afternoon...
Strong surface heating to the west and south of ongoing storm
clusters in northern and eastern AL will contribute to
destabilization and the potential for stronger storms within the
clusters that will spread south/southwestward through the afternoon. Precipitation loading and steepening low-level lapse rates could
support isolated downbursts and wind damage with the strongest
storms.

..Thompson/Chalmers.. 07/19/2026

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Sun Jul 19 19:56:00 2026

ACUS01 KWNS 191955
SWODY1
SPC AC 191953

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0253 PM CDT Sun Jul 19 2026

Valid 192000Z - 201200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE
NORTHERN PLAINS AND PARTS OF THE SOUTHEAST AND MID-ATLANTIC...

...SUMMARY...
Scattered damaging wind gusts are possible this afternoon over
portions of the Southeast. Scattered severe thunderstorms capable
of severe wind gusts and large hail are possible late this afternoon
through tonight from the Dakotas into Minnesota.

...20z Update...
The previous forecast largely remains on track with only minor
adjustments made based on recent convective trends and latest
high-res ensemble guidance.

...Georgia and Mid-Atlantic...
Across northern Georgia, convection has thus far exhibited mostly
pulse-like behavior with transient and weak updrafts. Regional
velocity imagery shows occasional swaths of strong winds embedded
within downbursts, so some localized damaging wind threat will
likely persist across the region through early evening given hot
low-level conditions surrounding ongoing storms. However, based on
these observed trends, limited clustering, and weak convective
signals in latest guidance, the 15% wind probabilities have been
trimmed eastward to align with more favorable thermodynamic
conditions (particularly steeper low-level lapse rates) and where
guidance continues to show some thunderstorm potential through late
afternoon. See MCD #1660 for additional near-term forecast
information.

Further east, a mix of thunderstorm clusters and loosely organized
cells has been observed with occasional reports of wind damage noted
over the past few hours. Based on recent mesoanalyses, the best
thermodynamic and kinematic environment remain across eastern VA/NC,
and consideration was made for introducing 5% hail probabilities.
However, MRMS VIL/MESH trends show relatively transient and weak
hail cores, suggesting that damaging winds will remain the
predominant threat through early evening.

...Northern High Plains...
Latest HRRR/RRFS time-lagged ensembles continue to show a strong
signal for severe wind across south-central ND and far northern SD
later this evening as thunderstorms develop along the approaching
cold front. Observational trends seem to support this as low 70
dewpoints continue to spread north into ND and pre-frontal cumulus
begins to develop along the western SD/ND border. Aside from minor
adjustments of probability/intensity lines to better align with
recent guidance and satellite trends, forecast thoughts outlined in
the previous discussion (below) remain on track.

..Moore.. 07/19/2026

.PREV DISCUSSION... /ISSUED 1124 AM CDT Sun Jul 19 2026/

...Dakotas/MN this afternoon into tonight...
A midlevel trough over southern SK will suppress the northern extent
of the ridge over the Great Plains as an associated surface
trough/front moves into ND this afternoon. Strong surface
heating/mixing and weak ascent along the wind shift could support
thunderstorm development after about 22z beginning in south central
ND and expanding into northern SD and northeast ND through late
evening. The initial storms will be relatively high based with
forecast hodographs favoring splitting supercells capable of
producing significant outflow gusts (80+ mph) and isolated very
large hail (2-3+ inch diameter). Storms are expected to evolve into
a cluster or two tonight while spreading east-southeastward toward
western MN with a continued threat for occasional severe outflow
gusts and large hail.

...Carolinas and vicinity this afternoon/evening...
A weak cold front will continue to drift southward across VA/KY
toward NC through the afternoon, in association with the southern
periphery of a midlevel trough moving over the Mid-Atlantic and
southern New England. The southern extent of ~30 kt midlevel flow
overlaps the baroclinic zone and northern extent of the unstable
warm sector. Though midlevel lapse rates are not steep per 12z
soundings, surface temperatures warming into the 90-95 F range with
dewpoints in the low-mid 70s will drive MLCAPE of 2500-3500 J/kg
with negligible convective inhibition and steepening low-level lapse
rates. Scattered thunderstorm development is likely by early-mid
afternoon along the differential heating zone near the cold front,
as well as along a subtle surface trough across eastern NC.
Multicell clusters are the primary expected storm mode with the
potential to produce occasional wind damage with downbursts this afternoon/evening. Vertical shear will be a little stronger across
southeast VA/northeast NC where some storm organization will be
possible.

...Tropical Depression 2 in the eastern Gulf...
NHC has initiated advisories on Tropical Depression 2 in the eastern
Gulf, centered roughly 130 n mi west of Tampa as of 15z. Though
some outer eastern bands will affect the FL Gulf coast this
afternoon, it appears that enhancements to flow/shear are too
marginal to support any substantial threat of outer band
supercells/tornadoes along the FL Gulf coast through tonight.
Still, isolated strong outflow gusts will be possible with broken
thunderstorm bands this afternoon/evening across central/north FL
and south GA.

...AL area this afternoon...
Strong surface heating to the west and south of ongoing storm
clusters in northern and eastern AL will contribute to
destabilization and the potential for stronger storms within the
clusters that will spread south/southwestward through the afternoon. Precipitation loading and steepening low-level lapse rates could
support isolated downbursts and wind damage with the strongest
storms.

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Mon Jul 20 01:07:40 2026

ACUS01 KWNS 200107
SWODY1
SPC AC 200105

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0805 PM CDT Sun Jul 19 2026

Valid 200100Z - 201200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE DAKOTAS/UPPER MIDWEST...

...SUMMARY...
Scattered severe thunderstorms capable of large hail and wind gusts
will remain possible mainly across the Dakotas into Minnesota.

...Northern Plains/Upper Midwest...
Severe thunderstorms including some supercells will continue to
focus this evening across the Dakotas, primarily across
south-central/eastern North Dakota as well as north-central/eastern
South Dakota, while also expanding into parts of Minnesota tonight.
Bouts of large hail will remain possible along with severe-caliber
wind gusts. This will be as storms progress east-southeastward with
the primary moisture/instability axis, supported by an amplifying
shortwave trough over Saskatchewan toward Manitoba, and the
development of a modest-strength southwesterly low-level jet across
the Upper Midwest tonight.

...Carolinas/Mid-Atlantic States...
A few strong/locally severe storms could still occur this evening,
but overall storm intensifies are expected to continue to wane with
the loss of daytime heating.

..Guyer.. 07/20/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Mon Jul 20 06:04:32 2026

ACUS01 KWNS 200604
SWODY1
SPC AC 200602

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0102 AM CDT Mon Jul 20 2026

Valid 201200Z - 211200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS
OF THE UPPER MIDWEST AND GREAT LAKES...

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS NORTH
CAROLINA AND FAR SOUTHERN VIRGINIA...

...SUMMARY...
Severe thunderstorms are expected across portions of the Upper
Midwest and Great Lakes vicinity, especially late this afternoon and
tonight. Swaths of damaging winds, large hail, and a few tornadoes
will all be possible. Isolated damaging wind gusts may also occur
over parts of the Carolinas and southern Virginia.

...Upper Midwest/Great Lakes...
A potentially active severe-weather scenario is expected later today
into tonight, although some key uncertainties persist related to the
potential impacts of early day convection and associated cloud
debris.

A substantial shortwave trough over southern Manitoba will continue
to gradually amplify and spread southeastward to the Lake Superior
vicinity through tonight, with a strengthening belt of
mid/high-level west-northwesterly flow overspreading the Upper
Midwest toward the Lake Michigan vicinity, highlighted by 50-70 kt
mid-level winds and 100 kt winds in the upper levels across Minnesota/Wisconsin. An east/southeastward-advecting plume of steep
mid-level lapse rates will overspread a warm sector with upper 60s
to lower/middle 70s F dewpoints.

Initially, a few early day storms could produce hail and perhaps
some strong wind gusts across east/southeast Minnesota into western
Wisconsin and eastern Iowa, amidst ample elevated instability and
effective shear over 50 kt. This activity may continue to spread
southeastward this morning but tend to wane during the day, leading
to a potential regional break prior to additional/more vigorous
development by late afternoon along the cold front as it progresses east-southeastward toward Wisconsin/Upper Michigan and
northern/eastern Iowa.

The initial storms should primarily be supercells given such strong
deep-layer shear. A corridor of large hail and tornado risk is
evident east of the instability axis from Iowa across Wisconsin into
Upper MI. Even while near-surface winds may tend to veer with time,
effective SRH may exceed 300 m2/s2, especially across Wisconsin
toward Upper Michigan as supported by the seasonally very-strong 2-3
km AGL winds (700 mb winds in excess of 50 kt). The degree of SRH
could support a couple strong tornadoes (EF2+), and somewhat higher
tornado probabilities could be warranted in subsequent outlooks as
early day convection details are resolved. While supercells will
persist for a time, several storm clusters will evolve this evening,
with a continued damaging wind and some tornado risk persisting
southeastward this evening prior to storm intensity eventually
waning overnight.

...Carolinas and southern Virginia...
Convection and related cloud debris may persist early today, but a
moist air mass will again diurnally destabilize this afternoon along
and south of a roughly west/east-oriented front. Daytime heating,
70s F dewpoints and surface convergence will aid storm formation and intensification this afternoon. MLCAPE in excess of 2000 J/kg, PWAT
over 2.00", and mid-level westerly flow aloft of 15-20 kt will lead
to multicellular storm mode with isolated damaging wind gusts during
the afternoon until around sunset.

...Florida...
Tropical Depression Two may gradually strengthen across the
northeast Gulf of America today and tonight. Reference the National
Hurricane Center for the latest development/forecast details. While
various global models support the notion of a strengthening of
southerly winds in the lowest 2-3km AGL, especially across the
western Florida Peninsula, it currently appears that
supercell-related tornado potential should remain low, largely
attributable to the overall weakness of the Depression and weak wind
aloft.

..Guyer/Weinman.. 07/20/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Mon Jul 20 12:20:04 2026

ACUS01 KWNS 201219
SWODY1
SPC AC 201218

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0718 AM CDT Mon Jul 20 2026

Valid 201300Z - 211200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS
OF THE UPPER MIDWEST AND GREAT LAKES...

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS NORTH
CAROLINA AND FAR SOUTHERN VIRGINIA...

...SUMMARY...
Severe thunderstorms are expected across portions of the Upper
Midwest and Great Lakes vicinity, especially late this afternoon and
tonight. Swaths of damaging winds, large hail, and a few tornadoes
will all be possible. Isolated damaging wind gusts may also occur
over parts of the Carolinas and southern Virginia.

...Upper Midwest/Great Lakes...
Radar/IR satellite composite this morning shows a decaying MCS over
far northern IA into west-central WI with warm-advection-related
storms moving east-southeast atop the MCS cold pool. This
convective activity is occurring downstream of a seasonably potent
mid-level shortwave trough and associated jet streak.

Surface analysis this morning places a front over the mid MS Valley
extending north-northwest and intersecting an outflow boundary over
southwest MN. A surface low over western ON is forecast to develop
east across north-central ON as an attendant cold front pushes
southeast across the Upper Midwest. The front over the mid- to
upper MS Valley will advance northeast as a warm front and the warm
sector will become increasingly narrow with northward extent in the
northern WI vicinity.

A warm and seasonably moist airmass will advect northeast into WI in
wake of the morning showers/thunderstorms, while a plume of elevated mixed-layer air overspreads the region from the west. Models
generally show upper 60s to lower/middle 70s F surface dewpoints
contributing to a very unstable boundary layer by mid-late
afternoon. However, considerable uncertainty remains regarding
details with this forecast update due in part to the morning
convection and downstream destabilization/hazard specifics for later
this afternoon/evening.

It is plausible the initial storms that develop later this afternoon
will quickly organize into supercells given strong deep-layer shear
and ample buoyancy ahead of the cold front. In agreement with prior
forecast thinking, a corridor of large hail and tornado risk will
extend from Iowa across Wisconsin into Upper MI. Forecast soundings
show elongated hodographs with 35-50 kt 700 mb flow, which will act
to enlarge hodographs and perhaps support a couple of strong
tornadoes. However, will defer any potential severe changes to
later outlook updates if greater confidence and morning convective
details are resolved. Eventually, a few clusters will probably
evolve this evening, with a continued damaging wind and some tornado
risk persisting southeastward before eventually waning overnight.

...Carolinas and southern Virginia...
Strong heating to the south of a west-east oriented stalled front
will contribute to moderate buoyancy by early to mid afternoon.
Rich low-level moisture (surface dewpoints in the 70s F) and moist
tropospheric profiles will yield high PW and the potential for
water-loaded downdrafts with the more intense thunderstorm cores.
Scattered thunderstorms with an isolated to scattered wind-damage
threat will probably focus during the 18-00 UTC period.

...Florida...
Tropical Depression Two is forecast to slowly intensify across the
northeast Gulf of America today and tonight (refer to NHC's latest
forecast details). Model guidance shows some gradual strengthening
of 2-3km AGL flow, especially across the western Florida Peninsula.
Yet, forecast soundings imply the possibility for transient
supercell structures will likely be limited/low due to substantially
weaker flow in the midlevels---precluding a low-severe highlight at
this time.

..Smith/Broyles.. 07/20/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Mon Jul 20 16:32:36 2026

ACUS01 KWNS 201632
SWODY1
SPC AC 201630

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1130 AM CDT Mon Jul 20 2026

Valid 201630Z - 211200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON
INTO EARLY TONIGHT FROM EASTERN IOWA AND NORTHWESTERN ILLINOIS
ACROSS WISCONSIN INTO WESTERN UPPER MICHIGAN...

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON
ACROSS CENTRAL NORTH CAROLINA...

...SUMMARY...
Severe thunderstorms are expected across portions of the Upper
Midwest and Great Lakes vicinity, especially late this afternoon
into late evening. A few strong-intense tornadoes, swaths of
damaging winds, and isolated very large hail will all be possible.
Isolated damaging gusts may also occur over parts North Carolina
this afternoon.

...Upper Midwest through tonight...
A midlevel shortwave trough is cresting the ridge and will turn
southeastward today while moving over the upper MS Valley, as an
associated cold front likewise moves southeastward into Upper MI, WI
and IA. Earlier storms in Upper MI have weakened, while a cluster
is ongoing in eastern IA. Destabilization will occur in the wake of
the eastern IA storms as a reservoir of low-mid 70s boundary-layer
dewpoints spreads northeastward from IA/southern MN into WI and
western Upper MI. The low-level moistening will occur beneath a
plume of midlevel lapse rates greater than 8 C/km and in tandem with
surface heating in cloud breaks, all of which will drive MLCAPE in
excess of 3000 J/kg. As is typical with lingering morning
convection, there is some uncertainty regarding the specific
locations of afternoon storm development in its wake. Wind profiles
will favor supercells as the initial storm mode this afternoon along
and just ahead of the cold front, given very long hodographs
oriented largely orthogonal to the front. Low-level shear/hodograph
curvature will also be substantial, which combined with the moist
boundary layer, steep lapse rates and large buoyancy will support
the potential for a few strong-intense tornadoes. Very large hail
will be possible with the more discrete supercells, while
significant severe outflow gusts will be possible with any
clustering of storms later this afternoon/evening.

Initial supercells will likely evolve into a cluster or two by early
tonight while spreading southeastward across eastern IA, northern
IL, northwest IN and Lower MI with a continued threat for occasional
wind damage and isolated large hail.

...Central NC area this afternoon/evening...
Thunderstorm development is expected again this afternoon along a
stalled front/differential heating zone across NC, to the west of
the more persistent cloud cover in far eastern NC. NC remains near
the south edge of the midlevel westerlies, with mid 70s
boundary-layer dewpoints coincident with temperatures at or above 90
F contributing to MLCAPE in excess of 2000 J/kg. A few damaging
downbursts will be possible with precipitation-loaded downdrafts in
an environment with steepening low-level lapse rates.

...FL Big Bend today...
Tropical Depression #2 is forecast to drift slowly westward across
the northeast Gulf through tomorrow and become a tropical storm.
Though deep-layer wind profiles are not particularly favorable in
the northeast quadrant of the cyclone, where winds aloft are from
the northeast, there is just enough low-level shear to support
weakly rotating storms in the outer convective bands. An isolated tornado/waterspout or two may occur today in coastal areas of the FL
Big Bend.

..Thompson/Chalmers.. 07/20/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Mon Jul 20 19:59:36 2026

ACUS01 KWNS 201959
SWODY1
SPC AC 201957

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0257 PM CDT Mon Jul 20 2026

Valid 202000Z - 211200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS
OF THE UPPER MIDWEST...

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS CENTRAL
NORTH CAROLINA...

...SUMMARY...
Severe thunderstorms are expected across portions of the Upper
Midwest and Great Lakes vicinity, especially late this afternoon
into late evening. A few strong-intense tornadoes, swaths of
damaging winds, and isolated very large hail will all be possible.
Isolated damaging gusts may also occur over parts of North Carolina
this afternoon.

...20z Update...
The previous forecast largely remains on track with only minor
adjustments made. Recent GOES imagery and surface observations show
gradually building cumulus across eastern MN into northwest WI along
a diffuse surface cold front. Latest high-res guidance suggests this
will be the primary initiation zone over the next few hours, which
increases confidence in the downstream severe threat and implies the
severe threat is diminishing for areas further west. Risk
probabilities were trimmed across northeast MN to reflect this
trend. Elevated convection migrating across southeast MN/WI are
indicative of steeper mid-level lapse rates (observed in upstream 18
UTC soundings) spreading east in the wake of this morning's weak
MCS. This, coupled with steady warming/moistening of the low-level
air mass and 50-60 knot mid-level flow observed by the KMPX and KDVN
VWPs, lends confidence in the ongoing forecast for much of the
region. See the previous discussion (below) and MCD #1674 for
additional forecast details.

...North Carolina...
Ongoing thunderstorms have exhibited pulse-like behavior over the
past few hours across NC and adjacent areas. While much of this
activity has been sub-severe, low-level thermodynamic conditions
will remain favorable through early evening for strong to severe
downburst winds. Given the ongoing coverage of convection across
north-central NC, 15% risk probabilities were maintained.

Elsewhere, more isolated strong/severe winds appear possible across
northeast ND/northwest MN as a pocket of colder mid-level
temperatures coincident with 30-40 knot low-level winds overspreads
the region in tandem with the primary mid/upper-level trough.
Similarly, very sporadic severe gusts associated with downbursts
within a deeply-mixed environment are possible across
central/southern AZ, as well as northern FL/far southern GA where
local velocity data shows embedded swaths of strong winds associated
with the outer convective bands of Tropical Depression 2. However,
all of these regions, the kinematic/thermodynamic environments
appear fairly marginal and/or convective signals in recent ensemble
guidance are too weak to warrant severe wind highlights.

..Moore.. 07/20/2026

.PREV DISCUSSION... /ISSUED 1130 AM CDT Mon Jul 20 2026/

...Upper Midwest through tonight...
A midlevel shortwave trough is cresting the ridge and will turn
southeastward today while moving over the upper MS Valley, as an
associated cold front likewise moves southeastward into Upper MI, WI
and IA. Earlier storms in Upper MI have weakened, while a cluster
is ongoing in eastern IA. Destabilization will occur in the wake of
the eastern IA storms as a reservoir of low-mid 70s boundary-layer
dewpoints spreads northeastward from IA/southern MN into WI and
western Upper MI. The low-level moistening will occur beneath a
plume of midlevel lapse rates greater than 8 C/km and in tandem with
surface heating in cloud breaks, all of which will drive MLCAPE in
excess of 3000 J/kg. As is typical with lingering morning
convection, there is some uncertainty regarding the specific
locations of afternoon storm development in its wake. Wind profiles
will favor supercells as the initial storm mode this afternoon along
and just ahead of the cold front, given very long hodographs
oriented largely orthogonal to the front. Low-level shear/hodograph
curvature will also be substantial, which combined with the moist
boundary layer, steep lapse rates and large buoyancy will support
the potential for a few strong-intense tornadoes. Very large hail
will be possible with the more discrete supercells, while
significant severe outflow gusts will be possible with any
clustering of storms later this afternoon/evening.

Initial supercells will likely evolve into a cluster or two by early
tonight while spreading southeastward across eastern IA, northern
IL, northwest IN and Lower MI with a continued threat for occasional
wind damage and isolated large hail.

...Central NC area this afternoon/evening...
Thunderstorm development is expected again this afternoon along a
stalled front/differential heating zone across NC, to the west of
the more persistent cloud cover in far eastern NC. NC remains near
the south edge of the midlevel westerlies, with mid 70s
boundary-layer dewpoints coincident with temperatures at or above 90
F contributing to MLCAPE in excess of 2000 J/kg. A few damaging
downbursts will be possible with precipitation-loaded downdrafts in
an environment with steepening low-level lapse rates.

...FL Big Bend today...
Tropical Depression #2 is forecast to drift slowly westward across
the northeast Gulf through tomorrow and become a tropical storm.
Though deep-layer wind profiles are not particularly favorable in
the northeast quadrant of the cyclone, where winds aloft are from
the northeast, there is just enough low-level shear to support
weakly rotating storms in the outer convective bands. An isolated tornado/waterspout or two may occur today in coastal areas of the FL
Big Bend.

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Tue Jul 21 01:02:08 2026

ACUS01 KWNS 210101
SWODY1
SPC AC 210100

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0800 PM CDT Mon Jul 20 2026

Valid 210100Z - 211200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE UPPER GREAT LAKES INTO THE LOWER MISSOURI VALLEY...

...SUMMARY...
Severe thunderstorms capable of producing damaging wind gusts,
severe hail, and a couple of tornadoes will continue across portions
of the Upper Great Lakes and Lower Missouri Valley through late
tonight.

...01Z Update...
Water-vapor imagery and VWP data indicate a robust midlevel wave and accompanying belt of 50-60-kt west-northwesterly flow overspreading
the Upper Midwest, and this feature will continue east-southeastward
across the Great Lakes region tonight. In the low-levels, an
attendant cold front will continue east-southeastward across this
region as well. In the Upper Great Lakes and Midwest, 50-60 kt of
deep-layer shear (sampled by regional VWPs) oriented perpendicular
to the cold front and a relatively narrow corridor of strong
pre-frontal buoyancy (around 3000 J/kg MLCAPE) will continue to
promote semi-discrete supercell structures. Locally damaging wind
gusts, severe hail, and a couple of tornadoes will be possible with
this activity, given ample low-level hodograph curvature (around 250
m2/s2 effective SRH) beneath the core of a 40-kt LLJ. This activity
will generally spread east-southeastward across parts of Lower MI
tonight, where a continued risk of damaging wind gusts, severe hail,
and a tornado or two will continue ahead of the cold front before
encountering increasingly stable air.

Farther south, a couple organized clusters are tracking southward
across parts of southern IA and western IL. Given strong cold pools
with this activity, the primary concern will be severe wind gusts
and isolated/sporadic hail. These storms will continue tracking south-southeastward along a surface-based buoyancy gradient before
gradually weakening overnight.

..Weinman.. 07/21/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Tue Jul 21 06:01:14 2026

ACUS01 KWNS 210600
SWODY1
SPC AC 210559

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1259 AM CDT Tue Jul 21 2026

Valid 211200Z - 221200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS
OF THE UPPER OHIO VALLEY INTO THE MID-ATLANTIC...

...SUMMARY...
Numerous severe thunderstorms are expected across a broad region
from the Ohio Valley into the Mid-Atlantic and Northeast today. All
severe hazards are possible, but swaths of damaging wind gusts
should be the primary severe risk during the afternoon and early
evening hours.

...Ohio Valley into the Mid-Atlantic...
A broad area of 40-50-kt midlevel west-southwesterly flow will
overspread the OH Valley into the Mid-Atlantic as a large-scale
trough shifts across the northeastern CONUS. Scattered to numerous thunderstorms are expected to develop ahead of an eastward-moving
cold front across the OH Valley and along a pre-frontal trough over
the Mid-Atlantic. In the base of the trough, a convectively
augmented midlevel impulse moving from the lower OH Valley into the Mid-Atlantic may also serve as a focus for convective development.

Diurnal heating within cloud breaks, combined with upper 60s to
lower 70s dewpoints, will support moderate surface-based instability
across the broad pre-frontal warm sector. The most favorable overlap
of this instability and 40-50 kt of effective shear is expected from
the lower OH Valley into the Mid-Atlantic, where a mix of organized
clusters and supercells should evolve and spread eastward through
the day. Swaths of damaging wind gusts will be the primary severe
hazard, though severe hail will also be possible with any sustained
supercells. Additionally, a gradually strengthening and expanding
30-kt low-level jet will contribute to clockwise-curved low-level
hodographs, and a few tornadoes may occur.

...Mid-South into the Tennessee Valley...
Greater instability is expected southwestward into portions of the
Mid-South and TN Valley, although somewhat weaker deep-layer shear
(around 30-40 kt of effective shear) may temper storm organization
compared to ares farther northeast. Nevertheless, widely scattered thunderstorms capable of organizing into multicell clusters and
occasional supercell structures will pose a risk of damaging wind
gusts and isolated severe hail ahead of the cold front during the
afternoon and early evening hours.

...Northeast...
Increasing midlevel height falls/forcing for ascent preceding the
upper trough will support scattered thunderstorm development near an
effective warm front moving northward across portions of the
Northeast. While poor midlevel lapse rates and weaker instability
should limit the overall severe risk compared to areas farther
south, around 40 kt of effective shear will still support organized
storm structures. Damaging wind gusts will be the primary concern,
though isolated severe hail and a tornado or two will also be
possible.

..Weinman/Jirak.. 07/21/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Tue Jul 21 12:59:10 2026

ACUS01 KWNS 211258
SWODY1
SPC AC 211257

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0757 AM CDT Tue Jul 21 2026

Valid 211300Z - 221200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE OHIO VALLEY TO MID-ATLANTIC STATES...

...SUMMARY...
Numerous severe thunderstorms are expected across a broad region
from the Ohio Valley to the Mid-Atlantic and Northeast States today
into tonight. Swaths of damaging wind gusts are expected to be the
most common impact, but some tornadoes are possible as well.

...Ohio Valley into the Mid-Atlantic and Northeast...
A broad area of 40-50-kt mid-level west-southwesterly flow will
overspread the Ohio Valley into the Mid-Atlantic/Northeast as a
large-scale trough amplifies and shifts across the northeastern
CONUS. Scattered to numerous thunderstorms are expected to develop
ahead of an eastward-moving cold front across the Ohio Valley and
along a pre-frontal trough over the Mid-Atlantic. In the base of the
trough, a convectively augmented mid-level impulse moving from the
lower Ohio Valley into the Mid-Atlantic may also serve as a focus
for convective development. Severe thunderstorm potential could
increase relatively early today across parts of Ohio into
Pennsylvania and western New York.

Diurnal heating within cloud breaks, combined with upper 60s to
lower 70s F dewpoints, will support at least moderate surface-based
instability across the broad pre-frontal warm sector. The most
favorable overlap of this instability and 40-50 kt of effective
shear is expected from the lower Ohio Valley into the Mid-Atlantic,
where a mix of organized clusters and supercells should evolve and
spread eastward through the day. Swaths of damaging wind gusts will
be the primary severe hazard, though severe hail will also be
possible with any initial/sustained supercells. Additionally, a
gradually strengthening and expanding 30-kt low-level jet will
contribute to clockwise-curved low-level hodographs, and a few
tornadoes may occur. This supercell related-tornado potential may
focus along the warm front into parts of the Northeast, and with
semi-discrete development later today focusing along the lee
trough/edge of higher terrain, although low-level shear/SRH will be
moderate in most of the open warm sector as well.

...Mid-South and the Tennessee Valley...
Greater instability is expected southwestward into portions of the
Mid-South and Tennessee Valley, although somewhat weaker deep-layer
shear (around 30-40 kt of effective shear) may temper storm
organization compared to areas farther northeast. Nevertheless,
widely scattered thunderstorms capable of organizing into multicell
clusters and occasional supercell structures will pose a risk of
damaging wind gusts and isolated severe hail ahead of the cold front
during the afternoon into evening.

...Gulf Coast...
Tropical Storm Bertha is expected to continue to drift northwest
then westward over the northern Gulf tonight from off the coast of
the Florida Panhandle toward the southern Mississippi coast and
coastal southeast Louisiana. Reference the National Hurricane Center
for the latest details. A strong low-level wind field will approach
these coastal areas later today and tonight. However, forecast SRH
should remain relatively modest inland with marginal thermodynamic
profiles aside from the rich boundary layer moisture. Any
Bertha-related mini-supercell potential is expected to focus
offshore in the open Gulf waters.

..Guyer/Broyles.. 07/21/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Tue Jul 21 16:20:52 2026

ACUS01 KWNS 211620
SWODY1
SPC AC 211618

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1118 AM CDT Tue Jul 21 2026

Valid 211630Z - 221200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE OHIO VALLEY TO MID-ATLANTIC STATES...

...SUMMARY...
Numerous severe thunderstorms are expected across a broad region
from the Tennessee and Ohio Valleys to the Mid-Atlantic and
Northeast States today into tonight. Swaths of damaging wind gusts
are expected to be the most common impact, but some tornadoes are
possible as well.

...Tennessee/Ohio Valley into the Mid-Atlantic and Northeast...
Recent satellite imagery reveals a shortwave trough moving quickly southeastward across the Upper Great Lakes region, embedded within
the upper troughing that covers much of eastern Canada and extends
down into the Ohio Valley. Moderate mid-level flow accompanies this
shortwave, with wind speeds greater than 50 kt sampled around 500 mb
on the 12Z ILX, DTX, ILN, and PIT soundings. The strongest flow was
sampled at ILX and DTX, and the expectation is for this stronger
flow to spread eastward today, moving in tandem with the progressive
shortwave.

Showers and thunderstorms are already ongoing downstream of this
shortwave, with the highest coverage along and near the pre-frontal
trough in Ohio. Recent surface analysis reveals a somewhat complex
boundary structure, with a wavy warm front, a diffuse pre-frontal
trough, and a cold front. Primary warm front appears to extend
west-to-east from southeast Ohio across southern Pennsylvania and
into northern New Jersey, far southern New York, and extreme
southwest Connecticut. The cold front arcs southwestward from
northern Lower Michigan through central Illinois and central
Michigan.

Highest overall coverage is anticipated along and ahead of the cold
front this afternoon through this evening, with additional
development expected farther east (from central Pennsylvania into
central Virginia) along the lee trough as well. Highest buoyancy is
expected along the western periphery of the cold front from central
into western Kentucky, where mid to upper 70s dewpoints are
anticipated amid temperatures in the upper 80s/low 90s. Strong
buoyancy is still anticipated across Ohio as well. Robust
thunderstorm development is expected along the front. Vertical shear
is robust enough for supercells, but linear forcing along the front
and strong downdraft production will likely lead to quick upscale
growth. In either convective mode, damaging gusts (with speeds from
55 to 70 mph) will be the primary risk, with brief tornadoes as a
secondary threat, and large hail tertiary.

Farther east, a similar convective environment exists, although with
slightly less buoyancy and deep-layer vertical shear. A more
outflow-dominant multicell mode is anticipated across the central
Virginia vicinity, with a trend towards a more organized mode
possible with northern extent. Primary risk will be damaging gusts,
including a few around 65 to 70 mph. A somewhat confined corridor of
greater tornado potential exists from the Hudson Valley vicinity
into western Massachusetts/Connecticut as the warm front lifts
northward. Here, enhanced vorticity along the boundary coupled with
stronger low-level southerly flow could support a few brief
tornadoes.

...Great Basin...
Scattered to numerous thunderstorms are expected across the Great
Basin today, supported by strong diurnal heating/mixing and moderate
mid-level moisture along the western periphery of the upper ridging
centered over the central Rockies. A few strong updrafts/downdrafts
are possible, with an attendant risk for strong to severe (i.e. 50
to 65 mph) wind gusts.

...Gulf Coast...
Tropical Storm Bertha is expected to continue to drift
west-northwestward over the northern Gulf tonight from off the coast
of the Florida Panhandle toward the southern Mississippi/southern
Alabama coast. Reference the National Hurricane Center for the
latest details.

A strong low-level wind field will approach these coastal areas
later today and tonight. However, as is typical for a westward
moving tropical cyclone, forecast SRH should remain relatively
modest inland. Given the marginal thermodynamic profiles (aside from
the rich boundary layer moisture) and limited SRH over land, any
Bertha-related mini-supercell potential is expected remain offshore.

..Mosier/Chalmers.. 07/21/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Tue Jul 21 20:10:44 2026

ACUS01 KWNS 212003
SWODY1
SPC AC 212001

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0301 PM CDT Tue Jul 21 2026

Valid 212000Z - 221200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM PORTIONS
OF THE NORTHEAST AND MID ATLANTIC TO THE OHIO VALLEY...

...SUMMARY...
Numerous severe thunderstorms are expected across a broad region
from the Tennessee and Ohio Valleys to the Mid-Atlantic and
Northeast States into tonight. Swaths of damaging wind gusts are
expected to be the most common impact, but some tornadoes and hail
are possible as well.

...20z Update Mid Atlantic and New England...
A complicated convective situation continues across the area with
numerous cluster of strong to severe storms ongoing from southern
NY/CT/MA to the DelMarVA. A diffuse warm frontal zone from the
Hudson valley to Long Island and the Atlantic coast has supported a
few instances of stronger rotating supercells and QLCS structures.
This focus may continue as additional more discrete storms approach
from northern NJ and eastern PA. Otherwise, clustering of storms
ahead of the cold front and across VA will pose a risk for damaging
gusts through this evening. The primary update to the outlook was to
lower probabilities behind the ongoing convection over NY and
northeast OH where the air mass has been partially overturned.
Isolated damaging gusts and some hail remain possible tonight.

...OH Valley...
A broken band of storms ahead of a cold front, extending into WV and
southwest PA should continue to track east/southeast through this
afternoon and into the evening hours. Strong northwesterly flow
aloft is supporting moderate deep-layer shear and a mixed mode of
supercells and clusters across southern IN/OH and into northern KY.
A primary risk for damaging winds is expected given upscale growth
as storm coverage increases. However, the large buoyancy (MLCAPE
3000-4000 J/kg) and some supercell structures could support large
hail. Some tornado potential will also exist with the semi-discreet
supercells and QLCS structures. This appears most likely near a
convective modified boundary from astern OH into WV and southwest
PA.

Storm coverage should continue to increase this afternoon across
western KY and the lower OH Valley. With a predominately linear
storm mode expected along the cold front, damaging winds are the
most likely hazard. The primary change to the probabilities was to
trim behind the front over OH/IN. See the prior outlook for more
information.

..Lyons.. 07/21/2026

.PREV DISCUSSION... /ISSUED 1118 AM CDT Tue Jul 21 2026/

...Tennessee/Ohio Valley into the Mid-Atlantic and Northeast...
Recent satellite imagery reveals a shortwave trough moving quickly southeastward across the Upper Great Lakes region, embedded within
the upper troughing that covers much of eastern Canada and extends
down into the Ohio Valley. Moderate mid-level flow accompanies this
shortwave, with wind speeds greater than 50 kt sampled around 500 mb
on the 12Z ILX, DTX, ILN, and PIT soundings. The strongest flow was
sampled at ILX and DTX, and the expectation is for this stronger
flow to spread eastward today, moving in tandem with the progressive
shortwave.

Showers and thunderstorms are already ongoing downstream of this
shortwave, with the highest coverage along and near the pre-frontal
trough in Ohio. Recent surface analysis reveals a somewhat complex
boundary structure, with a wavy warm front, a diffuse pre-frontal
trough, and a cold front. Primary warm front appears to extend
west-to-east from southeast Ohio across southern Pennsylvania and
into northern New Jersey, far southern New York, and extreme
southwest Connecticut. The cold front arcs southwestward from
northern Lower Michigan through central Illinois and central
Michigan.

Highest overall coverage is anticipated along and ahead of the cold
front this afternoon through this evening, with additional
development expected farther east (from central Pennsylvania into
central Virginia) along the lee trough as well. Highest buoyancy is
expected along the western periphery of the cold front from central
into western Kentucky, where mid to upper 70s dewpoints are
anticipated amid temperatures in the upper 80s/low 90s. Strong
buoyancy is still anticipated across Ohio as well. Robust
thunderstorm development is expected along the front. Vertical shear
is robust enough for supercells, but linear forcing along the front
and strong downdraft production will likely lead to quick upscale
growth. In either convective mode, damaging gusts (with speeds from
55 to 70 mph) will be the primary risk, with brief tornadoes as a
secondary threat, and large hail tertiary.

Farther east, a similar convective environment exists, although with
slightly less buoyancy and deep-layer vertical shear. A more
outflow-dominant multicell mode is anticipated across the central
Virginia vicinity, with a trend towards a more organized mode
possible with northern extent. Primary risk will be damaging gusts,
including a few around 65 to 70 mph. A somewhat confined corridor of
greater tornado potential exists from the Hudson Valley vicinity
into western Massachusetts/Connecticut as the warm front lifts
northward. Here, enhanced vorticity along the boundary coupled with
stronger low-level southerly flow could support a few brief
tornadoes.

...Great Basin...
Scattered to numerous thunderstorms are expected across the Great
Basin today, supported by strong diurnal heating/mixing and moderate
mid-level moisture along the western periphery of the upper ridging
centered over the central Rockies. A few strong updrafts/downdrafts
are possible, with an attendant risk for strong to severe (i.e. 50
to 65 mph) wind gusts.

...Gulf Coast...
Tropical Storm Bertha is expected to continue to drift
west-northwestward over the northern Gulf tonight from off the coast
of the Florida Panhandle toward the southern Mississippi/southern
Alabama coast. Reference the National Hurricane Center for the
latest details.

A strong low-level wind field will approach these coastal areas
later today and tonight. However, as is typical for a westward
moving tropical cyclone, forecast SRH should remain relatively
modest inland. Given the marginal thermodynamic profiles (aside from
the rich boundary layer moisture) and limited SRH over land, any
Bertha-related mini-supercell potential is expected remain offshore.

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Wed Jul 22 00:56:22 2026

ACUS01 KWNS 220056
SWODY1
SPC AC 220054

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0754 PM CDT Tue Jul 21 2026

Valid 220100Z - 221200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE LOWER
OHIO VALLEY INTO THE TENNESSEE VALLEY AND PARTS OF THE
MID-ATLANTIC...

...SUMMARY...
Scattered severe storms remains possible this evening within the
Tennessee Valley into the Mid-Atlantic. Damaging winds will be the
primary risk, though a couple of tornadoes could occur with the most
organized storms.

...Synopsis...
A notable shortwave tough will continue moving through the Mid-Atlantic/Northeast into tonight. Convective overturning from
earlier this afternoon has stabilized much of Pennsylvania/New York
into New England. Forcing for ascent from the shortwave trough and
the surface cold front will allow for isolated activity to persist
tonight. Wind damage remains possible. An MCV is evident in northern
Virginia. This will continue to promote storm development into parts
of the Mid-Atlantic. Earlier activity has reduced buoyancy, but flow
fields will increase as the trough continues to approach. Wind
damage will continue to be the main threat, though a couple of
tornadoes could occur with the strongest storms. MLCAPE of 3000+
J/kg is still present within the Tennessee Valley vicinity. A
cluster of storms north of Nashville will pose the greatest risk for
damaging winds as it tracks southward into the instability axis.
Other strong to severe storms may impact parts of the eastern Great
Basin. Severe wind gusts are the concern in that region.

..Wendt.. 07/22/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Wed Jul 22 05:52:48 2026

ACUS01 KWNS 220552
SWODY1
SPC AC 220550

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1250 AM CDT Wed Jul 22 2026

Valid 221200Z - 231200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE
SOUTHERN MID-ATLANTIC...

...SUMMARY...
Isolated to scattered storms are possible in the southern
Mid-Atlantic into New England this afternoon/evening. Damaging winds
are the primary concern. Isolated strong to severe wind gusts are
also possible in the central High Plains and central Oregon.

...Synopsis...
A upper trough will persist in the Northeast CONUS with a ridge
amplifying into the Northwest. An offshore upper low in the
Northwest will eject shortwave perturbations into Oregon/Washington.
At the surface, a cold front will move through New England. The
front will slow in the Mid-Atlantic during the afternoon before
moving southeast during the overnight.

...Mid-Atlantic into parts of Carolinas...
The cold front in this region is expected to slow/stall near the
Blue Ridge into eastern Maryland. Models suggest
clouds/precipitation will be likely in the vicinity of the
Virginia/North Carolina border. Mid-level forcing for ascent will be
weak at best and subtle mid-level warming is expected from far
southern Virginia into the Carolinas. Moderate to strong mid-level
winds will be in place with the strongest flow in Virginia/Maryland.
It is not clear how convection will evolve during the day/afternoon.
Storms could potentially continue from the morning into the
afternoon over portions of the region. There also is potential for
storms to develop along the cold front where there could potentially
be greater surface heating. In the Carolinas, the lack of ascent and
cloud cover concerns limit confidence in how many storms and how
strong they will become. Greater confidence in storm coverage exists
in Virginia into the DelMarVa where the Slight Risk has been
maintained. The kinematic environment will support occasionally
organized storms capable of damaging winds and perhaps a tornado or
two.

...New England...
A strong mid-level jet will be favorably timed during the afternoon, particularly for New Hampshire/Maine. As the cold front moves
through, scattered storms appear probable. Effective shear of 30-40
kt and strong upper-level winds will promote supercell structures.
The shear vector will have a large component parallel to the
north-south cold front so it is not clear how long discrete
structures can be maintained. Isolated damaging winds, marginally
severe hail, and perhaps a tornado would be possible. Some
consideration was given to a higher severe probabilities, but the
region will initially be in the wake of a shortwave trough and
thermodynamic profiles exhibit characteristics (e.g., mid-level
inversion, lowered equilibrium level) that limits confidence in how
many severe-caliber storms will exist.

Farther south and west, there is less signal for convective
development along the cold front. A Marginal risk has been
maintained this outlook cycle. Some risk for damaging winds would
exist if an isolated storm can develop along the front.

...Central High Plains...
Southeasterly surface winds will combine with increasingly westerly/northwesterly flow aloft to promote modest deep-layer shear
(around 30 kt 0-6 km) during the afternoon/evening. The development
of a weak lee low and low-level moisture moving northwest around the
Midwest anticyclone will aid in storm development within the region. Temperature-dewpoint spreads at the surface will allow for efficient
outflow production. A strengthening southeasterly low-level jet in
western Kansas may also help maintain convection farther east during
the evening. Severe wind gusts are possible with this activity.

...Oregon...
An upper-low will be positioned off the Northwest Coast. Subtle
ascent will help to initiate storms in parts of central Oregon
during the afternoon. Models are in strong agreement that scattered
storms will move northward into at least early evening. Strong
heating will lead to large temperature-dewpoint spreads at the
surface. Inverted-v thermodynamic profiles will promote a risk for
strong to severe wind gusts despite limited buoyancy and shear.

..Wendt/Weinman.. 07/22/2026

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Wed Jul 22 12:52:46 2026

ACUS01 KWNS 221252
SWODY1
SPC AC 221250

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0750 AM CDT Wed Jul 22 2026

Valid 221300Z - 231200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE
SOUTHERN MID-ATLANTIC AND MAINE...

...SUMMARY...
Isolated to scattered storms are possible across the Carolinas and
southern Mid-Atlantic, as well as New England this afternoon and
early evening, with damaging winds as the primary concern. Isolated
strong to severe wind gusts are also possible in the central High
Plains and central Oregon.

...Carolinas/Mid-Atlantic...
The region will influenced by the base of the eastern CONUS trough
and moderately strong belt of cyclonically curved westerlies,
although subtle mid-level warming is expected across the Carolinas
and southern Virginia. Storm redevelopment and re-intensification
today will tend to favor a persistent west-east zone of pre-frontal
convergence and existing convection across southern Virginia and
northern North Carolina, with additional development possible this
afternoon farther north closer to the southeastward-moving cold
front. Cloud breaks and a moisture-rich environment will support
moderate destabilization this afternoon. Around 30-40 kt of
effective shear will support some organized clusters and
conditionally support some supercells, especially with somewhat
stronger wind profiles with northward extent across southern/eastern
Virginia toward the Delmarva. Damaging winds are the most probable
severe hazard regionally, but some tornado risk may exist as well.

...New England...
A shortwave trough/moderately strong mid-level jet streak will be
favorably timed with diurnal destabilization during the afternoon,
particularly for New Hampshire into Maine. As the cold front
progresses eastward, scattered storms are expected to develop.
Effective shear of 30-40 kt and strong upper-level winds will
support the possibility of some supercells aside from organized
multicells. Damaging winds, marginally severe hail, and perhaps a
tornado are all possible this afternoon until around sunset.

...Central High Plains...
Southeasterly surface winds will combine with increasingly westerly/northwesterly flow aloft to promote modest deep-layer shear
(around 30 kt 0-6 km) during the afternoon/evening. The development
of a weak lee low and low-level moisture moving northwest around the
Midwest anticyclone will aid in storm development within the region. Temperature-dewpoint spreads at the surface will allow for efficient
outflow production. A strengthening southeasterly low-level jet
across western Kansas may also help maintain convection farther east
during the evening. Severe wind gusts are possible with this
activity.

...Oregon...
Weak height falls will influence the region via an upper low off the
coastal Pacific Northwest. Modest large-scale ascent and diurnal heating/orographic influences will contribute to thunderstorm
development across central Oregon during the afternoon. Large temperature-dewpoint spreads will promote a risk for strong to
severe wind gusts despite relatively limited overall buoyancy and
vertical shear.

...Gulf Coast...
Tropical Storm Bertha will continue to slowly drift westward across
the northern Gulf of America, grazing the southern Louisiana coast
through tonight. Several factors suggest that inland/near-shore
supercell potential will remain limited including an expected
gradual weakening of Bertha and poor thermal profiles inland where
southerly low-level winds will develop toward the coast on its
eastern periphery.

..Guyer/Broyles.. 07/22/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Wed Jul 22 16:23:18 2026

ACUS01 KWNS 221623
SWODY1
SPC AC 221621

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1121 AM CDT Wed Jul 22 2026

Valid 221630Z - 231200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS
AFTERNOON/EVENING FOR MAINE AND THE MID-ATLANTIC...

...SUMMARY...
Scattered storms are expected across the Carolinas and southern
Mid-Atlantic, as well as New England this afternoon and early
evening, with damaging winds as the primary concern. Isolated strong
to severe wind gusts are also possible in the central High Plains,
southeast Texas and central Oregon, where isolated large hail will
also be possible.

...Northern New England this afternoon...
Per water vapor imagery and morning upper air observations, a
pronounced midlevel trough will progress east-northeastward from
PA/NY/Saint Lawrence Valley toward New England through this
afternoon. An associated surface cold front will likewise move
eastward and provide a focus for thunderstorm development by early
afternoon into Maine. A few cloud breaks developing from
west-to-east through the afternoon will allow surface temperatures
to warm into the 70s with boundary-layer dewpoints in the mid 60s,
resulting in MLCAPE in the 1000-1500 J/kg range. Deep-layer, south-southwesterly shear will be sufficient for a mix of clusters
and supercells with a primary threat for occasional wind damage.

...Mid-Atlantic this afternoon/evening...
A pre-frontal band of convection is ongoing across southern VA, with
a narrow zone of stronger surface heating/destabilization to the
north of the thicker clouds from northern VA into MD/DE in advance
of a cold front moving across PA. The southern fringe of the
stronger (35-50 kt) midlevel flow extends to near the VA/NC border
on the south side of the thicker cloud band. The ongoing convection
is likely persist through the afternoon while spreading slowly
southward. Midlevel lapse rates will remain poor, but deep-layer
vertical shear will be sufficient for embedded/organized storms with
occasional wind damage. Low-level shear will be marginally
favorable for rotating storms and perhaps an isolated tornado.

...Southeast TX late this afternoon through late evening...
Strong surface heating is underway with a general confluence zone
near the TX/LA border well to the west of highly-sheared Tropical
Storm Bertha. As Bertha continues westward, this confluence zone
should support thunderstorm development into southeast TX late this
afternoon. Steering flow from the northeast at ~35 kt will favor
storm clusters moving southwestward into a hot, deeply mixed
boundary layer where buoyancy will be sufficient to maintain the
storm clusters into late evening. A few strong-severe outflow gusts
will be the main threats.

...Northeast CO and vicinity this afternoon/evening...
Low-level upslope flow on the cool side of a surface front, combined
with weak perturbations rotating around the northwest periphery of
the southern Plains midlevel high, will support afternoon
thunderstorm development over the foothills. The storms will spread east-southeastward onto the plains, with a tendency for clustering
with the potential for isolated severe outflow gusts.

...OR this afternoon/evening...
Along the northwest edge of the monsoonal moisture plume, a midlevel
shortwave trough will move northward from northern CA into OR. Weak
forcing for ascent combined with daytime heating over the higher
terrain will support scattered thunderstorms later this
afternoon/evening from the Cascades into central OR. An environment
with MLCAPE of 500-1000 J/kg, steepening low-level lapse rates and
effective bulk shear near 25 kt will support isolated strong outflow
gusts and marginally severe hail.

..Thompson/Chalmers.. 07/22/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Wed Jul 22 20:02:52 2026

ACUS01 KWNS 222002
SWODY1
SPC AC 222000

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0300 PM CDT Wed Jul 22 2026

Valid 222000Z - 231200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER PARTS OF
THE MID ATLANTIC AND NEW ENGLAND...SOUTHEAST TEXAS...THE CENTRAL
HIGH PLAINS AND CENTRAL OREGON....

...SUMMARY...
Isolated to widely scattered storms remain possible across the
Carolinas and southern Mid-Atlantic, as well as New England this
afternoon and early evening, with damaging winds as the primary
concern. Isolated strong to severe wind gusts are also possible in
the central High Plains, southeast Texas and central Oregon, where
isolated large hail will also be possible.

...20z Update New England...
A broken band of strong to occasionally severe convection remains
ongoing ahead of a progressive cold front over northern and eastern
New England this afternoon. Weak buoyancy, but fairly strong
deep-layer shear (35-45 kt) should support isolated hail, and
damaging winds with stronger clusters or supercell structures this
afternoon. A brief tornado also remains possible across northern ME
where low-level shear is locally stronger. The primary change this
outlook cycle was to lower overall severe probabilities and remove
them behind the front where the air mass has stabilized.

...Mid Atlantic and Carolinas...
Farther south, the cold front has become increasingly zonally
oriented and slowed as the upper trough has lifted away to the
northeast. A warm and very moist environment remains in place across southeastern VA into northern NC. However, poor mid-level lapse
rates and decreasing vertical shear have limited convective
organization and intensity. Some renewed intensity is possible along
the convectively modified boundary/differential heating axis along
the NC/VA border this afternoon and evening. However, the severe
threat (predominately damaging gusts) is expected to remain isolated
into this evening. Severe probabilities have been lowered and
adjusted to better match the main focal area for severe storms near
the VA/NC border through this evening.

Elsewhere, isolated severe gusts/hail remain possible over parts of
the central High Plains and the southeast TX. Isolated hail is also
possible over parts of central OR. Scattered storms are expected
late this afternoon through the evening. No changes were made to
theses areas, see the previous discussion for more information.

..Lyons.. 07/22/2026

.PREV DISCUSSION... /ISSUED 1121 AM CDT Wed Jul 22 2026/

...Northern New England this afternoon...
Per water vapor imagery and morning upper air observations, a
pronounced midlevel trough will progress east-northeastward from
PA/NY/Saint Lawrence Valley toward New England through this
afternoon. An associated surface cold front will likewise move
eastward and provide a focus for thunderstorm development by early
afternoon into Maine. A few cloud breaks developing from
west-to-east through the afternoon will allow surface temperatures
to warm into the 70s with boundary-layer dewpoints in the mid 60s,
resulting in MLCAPE in the 1000-1500 J/kg range. Deep-layer, south-southwesterly shear will be sufficient for a mix of clusters
and supercells with a primary threat for occasional wind damage.

...Mid-Atlantic this afternoon/evening...
A pre-frontal band of convection is ongoing across southern VA, with
a narrow zone of stronger surface heating/destabilization to the
north of the thicker clouds from northern VA into MD/DE in advance
of a cold front moving across PA. The southern fringe of the
stronger (35-50 kt) midlevel flow extends to near the VA/NC border
on the south side of the thicker cloud band. The ongoing convection
is likely persist through the afternoon while spreading slowly
southward. Midlevel lapse rates will remain poor, but deep-layer
vertical shear will be sufficient for embedded/organized storms with
occasional wind damage. Low-level shear will be marginally
favorable for rotating storms and perhaps an isolated tornado.

...Southeast TX late this afternoon through late evening...
Strong surface heating is underway with a general confluence zone
near the TX/LA border well to the west of highly-sheared Tropical
Storm Bertha. As Bertha continues westward, this confluence zone
should support thunderstorm development into southeast TX late this
afternoon. Steering flow from the northeast at ~35 kt will favor
storm clusters moving southwestward into a hot, deeply mixed
boundary layer where buoyancy will be sufficient to maintain the
storm clusters into late evening. A few strong-severe outflow gusts
will be the main threats.

...Northeast CO and vicinity this afternoon/evening...
Low-level upslope flow on the cool side of a surface front, combined
with weak perturbations rotating around the northwest periphery of
the southern Plains midlevel high, will support afternoon
thunderstorm development over the foothills. The storms will spread east-southeastward onto the plains, with a tendency for clustering
with the potential for isolated severe outflow gusts.

...OR this afternoon/evening...
Along the northwest edge of the monsoonal moisture plume, a midlevel
shortwave trough will move northward from northern CA into OR. Weak
forcing for ascent combined with daytime heating over the higher
terrain will support scattered thunderstorms later this
afternoon/evening from the Cascades into central OR. An environment
with MLCAPE of 500-1000 J/kg, steepening low-level lapse rates and
effective bulk shear near 25 kt will support isolated strong outflow
gusts and marginally severe hail.

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Thu Jul 23 01:03:00 2026

ACUS01 KWNS 230102
SWODY1
SPC AC 230100

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0800 PM CDT Wed Jul 22 2026

Valid 230100Z - 231200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE MID-ATLANTIC...MIDDLE TEXAS COAST...THE CENTRAL HIGH
PLAINS...AND CENTRAL OREGON...

...SUMMARY...
Isolated to widely scattered storms remain possible across the
Carolinas and southern Mid-Atlantic tonight, with damaging winds
being the primary concern. Isolated strong to severe wind gusts
remain possible in the central High Plains, Middle Texas Coast, and
central Oregon, where isolated hail will also be possible.

...Mid-Atlantic...
Disorganized/weak thunderstorms are ongoing within a pre-frontal
confluence zone extending from southeastern VA into western/central
NC. Over the next several hours, a southwesterly low-level jet will
strengthen to around 30 kt in advance of an approaching cold front.
Increasing convergence/low-level ascent and a warm/moist PBL (as
sampled by the MHX 00Z sounding) may support a modest uptick in
thunderstorm strength over the next several hours. Around 30 kt of
effective shear could promote loosely organized clusters, with the
primary concern being locally damaging wind gusts.

...Middle Texas Coast...
An organized cluster of storms with a history of producing severe
wind gusts is tracking southwestward along the Middle TX Coast. The
main severe risk will be associated with this activity as it
continues southwestward over the next few hours, given a very
moist/diurnally destabilized downstream air mass (lower 90s
temperatures amid lower 80s dewpoints) and around 30 kt of
northeasterly deep-layer shear (per the HGX VWP).

...Central High Plains...
In northeast CO, thunderstorm clusters are evolving
east-northeastward into a plume of increasingly rich PBL moisture
(upper 50s to lower 60s dewpoints) and a belt of modestly enhanced low/deep-layer shear along the northeastern periphery of a
large-scale ridge. This environment will continue to promote loosely
organized clusters capable of producing severe wind gusts. For more
details, see MCD #1713.

...Central Oregon...
A few loosely organized cells and clusters will continue tracking
northward across parts of central OR, where a belt of 30-kt midlevel
flow and a weakly unstable air mass will support isolated severe
wind gusts and hail with the stronger cores.

..Weinman.. 07/23/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Thu Jul 23 05:22:58 2026

ACUS01 KWNS 230522
SWODY1
SPC AC 230521

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1221 AM CDT Thu Jul 23 2026

Valid 231200Z - 241200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF
WESTERN KANSAS...

...SUMMARY...
Widely scattered severe storms capable of severe wind gusts and
large hail are possible over portions of the central and southern
High Plains Thursday afternoon and evening. More isolated
occurrences of damaging wind are possible from the middle Texas
coast into Deep South Texas, the eastern Carolinas, and parts of the
Columbia Basin into the northern Rockies.

...Synopsis...

A short-wave trough over the central Rockies late this evening is
forecast to progress slowly into the central High Plains by Thursday
afternoon, within the northeast periphery of a strengthening
mid/upper-level high over the southern Rockies. Downstream from
those developments, a short-wave trough will translate through New
England with a trailing vorticity ribbon and associated belt of
enhanced mid-level flow across the southern Mid-Atlantic. Elsewhere,
Tropical Storm Bertha is forecast to advance from just off the
southwest LA coast to the middle TX coast by Thursday evening.

At the surface, a stationary front currently extending from the CO
Front Range through the OK and TX Panhandles into the Red River
Valley is forecast to drift north through portions of western KS on
Thursday immediately ahead of a thermal low/lee cyclone over
southeast CO and southwest KS. A dryline will extend south from the
surface low-front triple point into the central or eastern OK and TX
Panhandles by mid- to late afternoon.

...Central and southern High Plains...

Strong boundary-layer heating is forecast in the vicinity of the
surface front and dryline Thursday afternoon with temperatures in
the mid 90s to around 105. The hot temperatures will combine with
dewpoints in the mid 50s to mid 60s and modestly steep mid-level
lapse rates to yield a narrow axis of moderate instability with
MLCAPE of 1500-2500 J/kg. Forcing for ascent preceding the
short-wave trough is expected to contribute to isolated to widely
scattered thunderstorms by mid afternoon from the vicinity of the
thermal low in southeast CO to along the front and dryline from
northeast CO into the OK and TX Panhandles.

Forecast soundings along the front indicate a vertically veering
wind profile with 30-35 kt of deep-layer shear, which will be
sufficient for at least episodic supercell structures with a risk
for large hail. In contrast, the storms forming in the hot, deeply
mixed air mass west of the boundary are more likely to produce
sporadic severe wind gusts. A corridor of potentially more
concentrated severe wind gusts may materialize across portions of
southwest KS by evening, where a number of the 00z CAMs indicate the
evolution of an organized cold pool.

...Middle Texas Coast to Deep South Texas...

A channel of enhanced mid-level flow is forecast to precede Bertha
atop a hot and moist boundary layer, with moderate instability
developing by afternoon along the middle TX coast. Similar to
Wednesday, widely scattered thunderstorms are expected during the
afternoon within an environment characterized by 30-40 kt of
deep-layer shear, steep low-level lapse rates, and high PW content.
As such, the potential will exist for locally damaging downburst
winds as storms spread southwest along the coast into Deep South TX
during the afternoon and evening hours.

...Columbia Basin into northern Rockies...

Mid/upper-level winds are forecast to strengthen across the area on
Thursday in tandem with a subtle disturbance moving through portions
of OR and WA. Daytime heating along favored terrain in conjunction
with the glancing influence of the passing disturbance will aid in
isolated to widely scattered thunderstorms by mid afternoon within a
moderately unstable and steep lapse rate environment. The
strengthening upper-level winds will enhance vertical shear,
supporting the potential for some storm organization with an
associated risk for locally damaging wind gusts and marginally
severe hail.

...Eastern Carolinas...

Thunderstorms are expected to be ongoing at 12Z Thursday along a west-to-east-oriented front in NC. Breaks in the clouds south of the
early-day storms will combine with a moist boundary layer to yield
an axis of moderate instability by afternoon across portions of
southeast NC into far eastern SC. A corridor of more concentrated
thunderstorm development is possible in that area, near the
intersection of the outflow from the morning storms with the
sea-breeze boundary. Modest deep-layer shear will coincide with
steepening low-level lapse rates and high PW content to yield
locally intense wet microbursts capable of damaging winds.

..Mead/Weinman.. 07/23/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Thu Jul 23 12:40:28 2026

ACUS01 KWNS 231240
SWODY1
SPC AC 231238

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0738 AM CDT Thu Jul 23 2026

Valid 231300Z - 241200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS WESTERN
KANSAS...

...SUMMARY...
Widely scattered severe storms capable of severe wind gusts and
large hail are possible over portions of the central and southern
High Plains this afternoon and evening. More isolated occurrences of
damaging wind are possible from the middle Texas coast into Deep
South Texas, the eastern Carolinas, and parts of the Columbia Basin
into the northern Intermountain region.

...Central/southern High Plains including western Kansas...
Strong boundary-layer heating is forecast in the vicinity of a High
Plains surface front and dryline this afternoon with temperatures
reaching the mid 90s to around 105 F. The hot temperatures will
combine with dewpoints in the mid 50s to mid 60s and modestly steep
mid-level lapse rates to yield a narrow axis of moderate instability
with MLCAPE of 1500-2500 J/kg across western Kansas southward into
western Oklahoma and the eastern Texas Panhandle. Forcing for ascent
preceding a shortwave trough is expected to contribute to isolated
to widely scattered thunderstorms by mid-afternoon from the vicinity
of the thermal low in southeast Colorado to along the front and
dryline from northeast Colorado into the Oklahoma/Texas Panhandles.

Forecast soundings along the front feature a vertically veering wind
profile with 30-35 kt of deep-layer shear, which will be sufficient
for at least episodic supercell structures with a risk
for large hail. In contrast, the storms forming in the hot, deeply
mixed air mass west of the boundary are more likely to produce
sporadic severe wind gusts. A corridor of more concentrated severe
wind gusts may materialize across portions of southwest Kansas by
evening, particularly if organized cold pool development occurs with
an evening time low-level jet increase.

...Middle Texas Coast to Deep South Texas...
As Bertha continues westward over the northwest Gulf, a belt of
enhanced mid-level flow will precede Bertha and spread atop a hot
and moist boundary layer inland, with moderate instability
developing by afternoon along the middle Texas coast. Similar to
Wednesday, widely scattered thunderstorms are expected during the
afternoon within an environment characterized by 30-40 kt of
deep-layer shear, steep low-level lapse rates, and high PW content.
As such, the potential will exist for locally damaging downburst
winds as storms spread west-southwestward along the coast into Deep
South Texas during the afternoon and evening.

...Columbia Basin/northern Intermountain West...
Weak height falls are expected while mid/upper-level winds
strengthen regionally ahead of an upper low off the coast of the
Pacific Northwest. Daytime heating along favored terrain, in
conjunction with the glancing influence of the passing disturbance,
will aid in isolated to widely scattered thunderstorms by
mid-afternoon within a moderately unstable and steep lapse rate
environment. The strengthening upper-level winds will enhance
vertical shear, supporting the potential for some storm organization
with an associated risk for locally damaging wind gusts and
marginally severe hail.

...Eastern Carolinas...
A very moist air mass and cloud breaks to the south of
front-associated convection early today across North Carolina should
allow for at least moderate destabilization across parts of the
coastal plain. This may result in a corridor of more concentrated
thunderstorm development, near the intersection of the outflow from
the morning storms with the sea-breeze boundary. Modest deep-layer
shear will coincide with steepening low-level lapse rates and high
PW content to yield locally intense wet microbursts capable of
damaging winds this afternoon until around sunset.

..Guyer/Broyles.. 07/23/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Thu Jul 23 16:20:24 2026

ACUS01 KWNS 231620
SWODY1
SPC AC 231618

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1118 AM CDT Thu Jul 23 2026

Valid 231630Z - 241200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR SOUTHWEST
KANSAS...

...SUMMARY...
Widely scattered severe storms capable of severe wind gusts and
large hail are possible over portions of the central and southern
High Plains this afternoon and evening. More isolated occurrences
of damaging wind are possible from the middle Texas coast into Deep
South Texas, the eastern Carolinas, and parts of the Columbia Basin
into the northern Intermountain region.

...Central/southern High Plains including western Kansas...
Surface analysis late this morning places a front draped from far
southwest KS extending into eastern CO. The front and a dryline
farther south will focus thunderstorm development later this
afternoon as strong heating results in appreciable boundary layer destabilization. Water-vapor imagery shows an impulse over central
CO moving slowly east to the north of a mid-level anticyclone
centered over northwest TX. This upper disturbance and associated
forcing for ascent coupled with weakening convective inhibition will
lead to scattered storms developing by late afternoon. Models
feature a vertically veering wind profile with 30-35 kt of
deep-layer shear over western KS near the front, which will be
sufficient for at least episodic supercell structures with a risk
for large hail. Some upscale growth into a small cluster may occur
during the evening as a southerly LLJ intensifies. Scattered severe
gusts will be possible with this activity. Farther west and south
along the dryline, a deeply mixed boundary layer and weaker shear
will favor an isolated risk for severe gusts with the stronger
downdrafts.

...Middle Texas Coast to Deep South Texas...
As Bertha continues westward over the northwest Gulf, a belt of
enhanced mid-level flow will precede Bertha and spread atop a hot
and moist boundary layer inland, with moderate instability
developing by afternoon along the middle Texas coast. Ample
deep-layer shear within the southwest quadrant of the parent system
may support some cold pool organization. Steepened low-level lapse
rates and high PW may yield a localized risk for severe gusts with
scattered storms that develop near the coast and move inland over
the coastal plain through the evening.

...Columbia Basin/northern Intermountain West...
Weak height falls are expected while mid/upper-level winds
strengthen regionally ahead of an upper low off the coast of the
Pacific Northwest. Daytime heating along favored terrain, in
conjunction with the glancing influence of the passing disturbance,
will aid in isolated to widely scattered thunderstorms by
mid-afternoon within a moderately unstable and steep lapse rate
environment. The strengthening upper-level winds will enhance
vertical shear, supporting the potential for some storm organization
with an associated risk for locally damaging wind gusts and
marginally severe hail.

...Eastern Carolinas...
Midday visible-satellite imagery shows scattered
showers/thunderstorms along a west-east oriented frontal zone over
southern NC. Cloud breaks south of convective cloud debris will
promote additional heating near the coast and moderate
destabilization by mid afternoon. A few of the stronger storms that
develop this afternoon into the early evening will probably pose a
localized risk for damaging gusts.

..Smith/Chalmers.. 07/23/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Thu Jul 23 19:41:04 2026

ACUS01 KWNS 231940
SWODY1
SPC AC 231939

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0239 PM CDT Thu Jul 23 2026

Valid 232000Z - 241200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF
SOUTHWEST KANSAS...

...SUMMARY...
Widely scattered severe storms capable of severe wind gusts and
large hail are possible over portions of the central and southern
High Plains this afternoon and evening. More isolated occurrences
of damaging wind are possible from the middle Texas coast into Deep
South Texas and parts of the Columbia Basin into the northern
Intermountain region.

...20z Update Carolinas...
A broad area of showers and thunderstorms is ongoing south of the quasi-stationary front across central NC. The environment south of
the boundary into SC is warm and moderately unstable. However,
vertical shear decreases substantially farther south from the
boundary. This has resulted in little storm organization thus far.
While sporadic damaging gusts remain possible, the tendency for
convection to focus along the boundary where there is less buoyancy
suggests severe potential is limited. 5% wind probabilities have
been removed with this update.

...Central and southern High Plains...
Scattered convection developing off the higher terrain and more
isolated development along the stalled surface front should
gradually coalesce across the High Plains late this afternoon into
this evening. With 30-35 kt of deep-layer shear near the front,
episodic supercell structures with a risk for large hail or damaging
gusts will be possible. Eventually, upscale growth into one or more
small clusters may occur during the evening as a southerly LLJ
intensifies. Scattered severe gusts will be possible with this
activity into the overnight hours.

...OR and ID...
Initial high-based thunderstorms are developing east of the upper
low over the Pacific Northwest. Enhanced southwesterly flow aloft,
and seasonably warm/moist conditions, associated with a plume of
monsoonal moisture, will support a risk for locally damaging wind
gusts and marginally severe hail this afternoon and evening. See
MCD#1716 for additional information.

..Lyons.. 07/23/2026

.PREV DISCUSSION... /ISSUED 1118 AM CDT Thu Jul 23 2026/

...Central/southern High Plains including western Kansas...
Surface analysis late this morning places a front draped from far
southwest KS extending into eastern CO. The front and a dryline
farther south will focus thunderstorm development later this
afternoon as strong heating results in appreciable boundary layer destabilization. Water-vapor imagery shows an impulse over central
CO moving slowly east to the north of a mid-level anticyclone
centered over northwest TX. This upper disturbance and associated
forcing for ascent coupled with weakening convective inhibition will
lead to scattered storms developing by late afternoon. Models
feature a vertically veering wind profile with 30-35 kt of
deep-layer shear over western KS near the front, which will be
sufficient for at least episodic supercell structures with a risk
for large hail. Some upscale growth into a small cluster may occur
during the evening as a southerly LLJ intensifies. Scattered severe
gusts will be possible with this activity. Farther west and south
along the dryline, a deeply mixed boundary layer and weaker shear
will favor an isolated risk for severe gusts with the stronger
downdrafts.

...Middle Texas Coast to Deep South Texas...
As Bertha continues westward over the northwest Gulf, a belt of
enhanced mid-level flow will precede Bertha and spread atop a hot
and moist boundary layer inland, with moderate instability
developing by afternoon along the middle Texas coast. Ample
deep-layer shear within the southwest quadrant of the parent system
may support some cold pool organization. Steepened low-level lapse
rates and high PW may yield a localized risk for severe gusts with
scattered storms that develop near the coast and move inland over
the coastal plain through the evening.

...Columbia Basin/northern Intermountain West...
Weak height falls are expected while mid/upper-level winds
strengthen regionally ahead of an upper low off the coast of the
Pacific Northwest. Daytime heating along favored terrain, in
conjunction with the glancing influence of the passing disturbance,
will aid in isolated to widely scattered thunderstorms by
mid-afternoon within a moderately unstable and steep lapse rate
environment. The strengthening upper-level winds will enhance
vertical shear, supporting the potential for some storm organization
with an associated risk for locally damaging wind gusts and
marginally severe hail.

...Eastern Carolinas...
Midday visible-satellite imagery shows scattered
showers/thunderstorms along a west-east oriented frontal zone over
southern NC. Cloud breaks south of convective cloud debris will
promote additional heating near the coast and moderate
destabilization by mid afternoon. A few of the stronger storms that
develop this afternoon into the early evening will probably pose a
localized risk for damaging gusts.

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Fri Jul 24 00:53:00 2026

ACUS01 KWNS 240052
SWODY1
SPC AC 240051

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0751 PM CDT Thu Jul 23 2026

Valid 240100Z - 241200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR A SMALL PART
OF SOUTHWEST KANSAS...

...SUMMARY...
Isolated strong to severe storms remain possible this evening across
parts of the central/southern High Plains, interior Northwest, and
south Texas.

...Southwest KS vicinity...
Convection may persist through much of the night across parts of
western KS, in response to a weak midlevel shortwave trough and
strengthening low-level jet. Veering wind profiles will provide
sufficient deep-layer shear for occasional storm organization,
though generally modest buoyancy and a tendency for much of the
convection to develop/persist to the cool side of increasing outflow
may tend to limit the coverage and magnitude of the severe threat. A
narrow corridor near and east of Dodge City appears to have the
greatest severe risk through dusk, though isolated severe gusts and
hail will continue to be possible across a larger portion of the central/southern High Plains through much of the evening.

...Interior Northwest...
Strong to locally severe storms remain possible early this evening
from eastern OR into southeast WA and western ID. Large-scale
forcing is not particularly strong, but MLCAPE approaching 1000 J/kg
and moderate deep-layer shear will continue to support occasional
storm organization, with a threat isolated hail and strong to severe
gusts. The threat should diminish later tonight with the onset of
nocturnal cooling/stabilization across the region.

...South Texas...
Tropical Depression Bertha is centered over the Houston vicinity
this evening. A continued weakening trend is expected through the
evening (reference NHC advisories for more information). To the
west/southwest of Bertha, modestly enhanced midlevel flow persists
this evening, per regional VWPs. Convection with locally damaging
gusts cannot be ruled out through dusk, with some threat possibly
persisting into late evening into parts of Deep South Texas.

..Dean.. 07/24/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Fri Jul 24 05:31:34 2026

ACUS01 KWNS 240531
SWODY1
SPC AC 240529

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1229 AM CDT Fri Jul 24 2026

Valid 241200Z - 251200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR
CENTRAL/EASTERN ND INTO PARTS OF NORTHERN MN...

...SUMMARY...
Severe thunderstorms capable of large to very large hail, damaging
wind, and possibly a tornado are forecast during the afternoon and
evening across portions of North Dakota into northern Minnesota.

...Dakotas into northern MN...
Within an amplifying upper-level pattern, multiple low-amplitude
midlevel shortwave troughs are forecast to move east-southeastward
from the northern Rockies toward ND and northern MN through the
period. A surface trough will trail southwestward from a deep
surface cyclone that will move from northern MB/ON towards Hudson
Bay. A plume of relatively steep midlevel lapse rates will
overspread a warm and moist boundary layer along/east of the surface
trough, with MLCAPE increasing above 2000 J/kg across parts of ND
into northwest MN by late afternoon. Strengthening mid/upper-level west-northwesterly flow will result in favorable deep-layer shear,
resulting in a conditionally favorable environment for severe
storms.

Guidance generally suggests that widely scattered storms will
develop along the surface trough by late afternoon across eastern
ND. Elongated hodographs and favorable instability will initially
favor supercell development, though some clustering will be possible
with time into the evening. Large to very large hail will be the
primary initial hazard. Some tornado potential could evolve with
persistent supercells, as low-level shear gradually increases from
late afternoon into the evening. Any organized clustering could
result in localized corridors of greater severe-wind potential. Some
severe threat could persist as storms move into a larger portion of northern/central MN through late evening, with a general weakening
trend expected late in the period due to increasing CINH and
weakening buoyancy.

Farther northwest, some guidance depicts isolated supercell
development west of the surface trough across the Canadian Prairies
during the late afternoon, which could then move into parts of
northern/central ND within a northwesterly flow regime. This
scenario is more uncertain, but 5% wind/hail probabilities have been
expanded westward in response to this potential.

...Coastal Carolinas vicinity...
Relatively strong heating of a richly moist airmass (PW above 2
inches) will result in the development of moderate buoyancy across
parts of the Coastal Carolinas and southeast GA, in the vicinity of
a surface front. Scattered storm development is expected by
early/mid afternoon. Deep-layer flow will generally be weak, but
locally damaging downbursts and outflow winds will be possible
within the warm and very moist environment.

...Southern High Plains vicinity...
A nearly stationary front draped from eastern NM into the TX/OK
Panhandles is expected to become a focus for thunderstorm
development by late afternoon or early evening. Buoyancy is forecast
to remain modest, and deep-layer flow will be weak, so organized
storm potential currently appears low. However, strong
boundary-layer heating/mixing will support potential for localized
downbursts. While magnitude and coverage of the threat currently
appear rather limited, wind probabilities may eventually be needed,
if confidence increases in more than very localized severe-wind
potential.

...Parts of the Great Basin into the Northern Rockies...
Widely scattered high-based storm development is expected this
afternoon from parts of the Great Basin into the northern Rockies,
along the periphery of an amplifying upper ridge over the Four
Corners region. Buoyancy and deep-layer shear are both expected to
remain weak, but strong to locally severe gusts will be possible
within the hot and well-mixed regime. Wind probabilities may
eventually be needed, if confidence increases in more than a very localized/transient severe-gust threat.

..Dean/Jirak.. 07/24/2026

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Fri Jul 24 12:50:06 2026

ACUS01 KWNS 241249
SWODY1
SPC AC 241248

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0748 AM CDT Fri Jul 24 2026

Valid 241300Z - 251200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE DAKOTAS
AND NORTHERN MINNESOTA...

...SUMMARY...
Severe thunderstorms capable of large to very large hail, damaging
winds, and a tornado risk are expected this afternoon and evening
across portions of North Dakota into northern Minnesota.

...Dakotas/northern Minnesota...
Within an amplifying upper-level pattern, multiple low-amplitude
mid-level shortwave troughs are forecast to move east-southeastward
from the northern Rockies toward North Dakota and northern Minnesota
through tonight. A surface trough will trail southwestward from a
deep surface cyclone that will move from northern Manitoba/Ontario
towards Hudson Bay. A plume of relatively steep mid-level lapse
rates will overspread a warm and moist boundary layer along/east of
the surface trough, with MLCAPE increasing above 2000 J/kg across
parts of North Dakota into northern Minnesota by late afternoon.
Strengthening mid/upper-level west-northwesterly flow will result in
favorable deep-layer shear, resulting in a conditionally favorable
environment for severe storms.

Guidance generally suggests that widely scattered storms will
develop along the surface trough by late afternoon across eastern
North Dakota into northwest Minnesota. Elongated hodographs and
favorable instability will favor supercell development, though some
clustering will be possible with time during the evening. Large to
very large hail will be the primary initial hazard. Some tornado
potential will exist with persistent supercells, as low-level
shear/SRH gradually increases onto the evening. Any organized
clustering could result in localized corridors of greater
severe-wind potential. Some severe threat could persist as storms
move into a larger portion of northern/central Minnesota through
late evening, with a general weakening trend expected overnight due
to increasing CINH and weakening buoyancy.

Farther northwest, some guidance depicts isolated supercell
development west of the surface trough across the Canadian Prairies
during the late afternoon, which could then move into parts of
northern/central North Dakota within a northwesterly flow regime.

...Coastal Carolinas vicinity...
Near/south of a residual front, relatively strong heating of a
richly moist airmass (PW above 2 inches) will result in the
development of moderate buoyancy across parts of the coastal
Carolinas and southeast Georgia. Scattered storm development is
expected by early/mid afternoon. Deep-layer flow will generally be
weak, but locally damaging downbursts and outflow winds will be
possible within the warm and very moist environment.

...Southern High Plains vicinity...
On the western periphery of residual early day precipitation/cloud
cover, a nearly stationary front draped from eastern New Mexico into
the Texas Panhandles is expected to become a focus for thunderstorm
development by late afternoon and early evening. While deep-layer
winds will be weak, strong boundary-layer heating/mixing will
support potential for localized downbursts.

...Parts of the Great Basin into the Northern Rockies...
Widely scattered high-based storm development is expected this
afternoon from parts of the Great Basin into the northern Rockies,
along the periphery of an amplifying upper ridge over the Four
Corners region. Buoyancy and deep-layer shear are both expected to
remain weak, but strong to locally severe gusts will be possible
within the hot and well-mixed regime. Current thinking is any such severe-caliber wind potential should remain very isolated and
somewhat marginal in nature.

..Guyer/Wendt.. 07/24/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Fri Jul 24 16:25:38 2026

ACUS01 KWNS 241625
SWODY1
SPC AC 241623

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1123 AM CDT Fri Jul 24 2026

Valid 241630Z - 251200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM CENTRAL NORTH
DAKOTA INTO NORTHERN MINNESOTA...

...SUMMARY...
Severe thunderstorms capable of large to very large hail, damaging
winds, and a tornado risk are expected this afternoon and evening
across portions of North Dakota into northern Minnesota.

...Dakotas/northern Minnesota...
Visible-satellite imagery late this morning shows a thin stratus
shield across central into northern MN ahead of a cluster of
thunderstorms over southern Manitoba. This thunderstorm activity is
associated with a weak mid-level vorticity max embedded within an
amplifying northwest-flow pattern over the Upper Midwest. A surface
trough extends southwestward into ND from a cyclone moving east
along the south shore of Hudson Bay.

A plume of relatively steep mid-level lapse rates will overspread a
warm and moist boundary layer along/east of the surface trough, with
MLCAPE increasing above 2000 J/kg across parts of North Dakota into
northern Minnesota by late afternoon. Forecast model soundings show
elongated hodographs thereby promoting storm organization, including
supercells and eventually a small cluster or two. Morning models
continue to indicate widely scattered (ND) to scattered storm
development (MN) later this afternoon into the evening. Large to
very large hail is possible with the supercells (1 to 3 inches in
diameter). Some tornado risk will likely focus across northern MN
where lower temperature-dewpoint spreads and enlarged hodographs
become co-located for a few hours. Any organized clustering could
result in localized corridors of greater severe-wind potential.
Some severe threat could persist as storms move into a larger
portion of northern/central Minnesota through late evening, with a
general weakening trend expected overnight due to increasing CINH
and weakening buoyancy.

Farther northwest, some guidance depicts isolated supercell
development west of the surface trough across the Canadian Prairies
during the late afternoon, which could then move into parts of
northern/central North Dakota within a northwesterly flow regime.

...Eastern ID into northeast NV...
A weak disturbance evident in water-vapor imagery will continue to
move northeast over northern UT into southeast ID this afternoon
along the periphery of the Four Corners upper ridge. Widely
scattered high-based storms will likely develop by late afternoon.
Forecast soundings show inverted-V profiles supporting ample
evaporative cooling with the stronger downdrafts. Isolated severe
gusts 60-70 mph are possible.

...Southern High Plains vicinity...
On the western periphery of residual early day precipitation/cloud
cover, a nearly stationary front draped from eastern New Mexico into
the Texas Panhandles is expected to become a focus for thunderstorm
development by late afternoon and early evening. While deep-layer
winds will be weak, strong boundary-layer heating/mixing will
support potential for localized downbursts.

...Southeast AZ...
Isolated to widely scattered storms are forecast to develop late
this afternoon and slowly propagate westward. A couple of the
stronger high-based downdrafts may yield a risk for severe gusts for
a few hours before this activity dissipates by late evening.

...Coastal Carolinas...
Near/south of a residual front, relatively strong heating of a
moisture-rich airmass will result in the development of moderate
buoyancy across the Carolina coastal plain. Scattered storm
development is expected by early/mid afternoon. A couple of
stronger water-loaded downdrafts may be capable of a localized
wind-damage risk.

..Smith/Moore.. 07/24/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Fri Jul 24 20:02:34 2026

ACUS01 KWNS 242002
SWODY1
SPC AC 242000

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0300 PM CDT Fri Jul 24 2026

Valid 242000Z - 251200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM CENTRAL NORTH
DAKOTA INTO NORTHERN MINNESOTA...

...SUMMARY...
Severe thunderstorms capable of large to very large hail, damaging
winds, and a tornado risk are expected this afternoon and evening
across portions of North Dakota into northern Minnesota.

...20z Update Northern Plains/Upper Midwest...
Scattered thunderstorms ongoing along a differential heating axis
near the international border should continue to increase in
coverage and intensity this afternoon. Aided by increasing synoptic
ascent and deep-layer shear from the approaching upstream
low-amplitude trough and jet, supercells and organized clusters are
likely. Severe hail is expected, with some 2-3+ inches in diameter
possible with the more robust supercells that evolve initially.
Damaging wind gusts are also likely across eastern ND into northern
MN as storms begin to grow upscale. A few significant gusts are
possible given the large buoyancy and plume of steeper low-level
lapse rates apparent to the southwest across ND.

A couple of tornadoes are possible closer to the effective boundary,
where lower temperature-dewpoint spreads and stronger low-level
shear are expected. A CIG-1 wind area was included where the latest
HRRR/RRFS time-lagged runs show greater clustering which could
promote a sustained damaging wind or hail threat into this evening.
See MCD#1622 for short-term information.

...Carolinas...
Scattered thunderstorms along a weak surface cold front and
sea-breeze boundary across the coast and coastal plain will continue
to pose a risk for isolated damaging gusts this afternoon. 5% wind probabilities were trimmed slightly to the west where storm
coverage/clustering are expected to be lower.

Elsewhere, the prior forecast remains valid with no changes.
Isolated severe wind gusts are possible over parts of TX, AZ and ID.
See the previous discussion and active mesoscale discussions for
more information.

..Lyons.. 07/24/2026

.PREV DISCUSSION... /ISSUED 1123 AM CDT Fri Jul 24 2026/

...Dakotas/northern Minnesota...
Visible-satellite imagery late this morning shows a thin stratus
shield across central into northern MN ahead of a cluster of
thunderstorms over southern Manitoba. This thunderstorm activity is
associated with a weak mid-level vorticity max embedded within an
amplifying northwest-flow pattern over the Upper Midwest. A surface
trough extends southwestward into ND from a cyclone moving east
along the south shore of Hudson Bay.

A plume of relatively steep mid-level lapse rates will overspread a
warm and moist boundary layer along/east of the surface trough, with
MLCAPE increasing above 2000 J/kg across parts of North Dakota into
northern Minnesota by late afternoon. Forecast model soundings show
elongated hodographs thereby promoting storm organization, including
supercells and eventually a small cluster or two. Morning models
continue to indicate widely scattered (ND) to scattered storm
development (MN) later this afternoon into the evening. Large to
very large hail is possible with the supercells (1 to 3 inches in
diameter). Some tornado risk will likely focus across northern MN
where lower temperature-dewpoint spreads and enlarged hodographs
become co-located for a few hours. Any organized clustering could
result in localized corridors of greater severe-wind potential.
Some severe threat could persist as storms move into a larger
portion of northern/central Minnesota through late evening, with a
general weakening trend expected overnight due to increasing CINH
and weakening buoyancy.

Farther northwest, some guidance depicts isolated supercell
development west of the surface trough across the Canadian Prairies
during the late afternoon, which could then move into parts of
northern/central North Dakota within a northwesterly flow regime.

...Eastern ID into northeast NV...
A weak disturbance evident in water-vapor imagery will continue to
move northeast over northern UT into southeast ID this afternoon
along the periphery of the Four Corners upper ridge. Widely
scattered high-based storms will likely develop by late afternoon.
Forecast soundings show inverted-V profiles supporting ample
evaporative cooling with the stronger downdrafts. Isolated severe
gusts 60-70 mph are possible.

...Southern High Plains vicinity...
On the western periphery of residual early day precipitation/cloud
cover, a nearly stationary front draped from eastern New Mexico into
the Texas Panhandles is expected to become a focus for thunderstorm
development by late afternoon and early evening. While deep-layer
winds will be weak, strong boundary-layer heating/mixing will
support potential for localized downbursts.

...Southeast AZ...
Isolated to widely scattered storms are forecast to develop late
this afternoon and slowly propagate westward. A couple of the
stronger high-based downdrafts may yield a risk for severe gusts for
a few hours before this activity dissipates by late evening.

...Coastal Carolinas...
Near/south of a residual front, relatively strong heating of a
moisture-rich airmass will result in the development of moderate
buoyancy across the Carolina coastal plain. Scattered storm
development is expected by early/mid afternoon. A couple of
stronger water-loaded downdrafts may be capable of a localized
wind-damage risk.

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Sat Jul 25 00:56:22 2026

ACUS01 KWNS 250055
SWODY1
SPC AC 250054

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0754 PM CDT Fri Jul 24 2026

Valid 250100Z - 251200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS
SOUTH-CENTRAL/EASTERN ND INTO NORTHERN MN AND EXTREME NORTHEAST
SD...

...SUMMARY...
Severe thunderstorms capable of large hail, damaging winds, and a
tornado risk remain possible this evening across portions of North
Dakota into northern Minnesota and extreme northeast South Dakota.

...ND into northern MN...
Scattered supercells are ongoing this evening across northern MN,
while a small storm cluster (with occasional embedded supercell
structures) is moving eastward across southeast ND and extreme
northeast SD. MLCAPE of 2000-3000 J/kg and effective shear of 40-50
kt will continue to provide a favorable environment for organized
storms through the evening, though some increase in CINH is expected
with time. Ongoing supercell structures will continue to pose a
threat of large hail and localized severe gusts, and some tornado
threat may persist through at least dusk, given increasing low-level
shear/SRH (as observed on the KMVX VWP). Any upscale growth could be accompanied by localized swaths of greater severe-wind threat. An
eventual weakening trend is expected late tonight, as CINH continues
to increase with time and buoyancy decreases with southeastward
extent. See MCD 1726 and MCD 1727 for more information.

...Elsewhere...
High-based convection may continue to pose a threat for localized
strong to severe gusts across parts of the southern Rockies and High
Plains, southeast AZ, and the northern Great Basin into parts of
ID/western WY/southwest MT though the evening. Weak deep-layer
flow/shear should continue to limit potential for a more organized
severe threat.

..Dean.. 07/25/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Sat Jul 25 05:58:12 2026

ACUS01 KWNS 250558
SWODY1
SPC AC 250556

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1256 AM CDT Sat Jul 25 2026

Valid 251200Z - 261200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF
CENTRAL MT...AND ALSO ACROSS PARTS OF SD...

...SUMMARY...
Storms with scattered severe wind gusts are possible across parts of
Montana and South Dakota this afternoon and evening.

...MT into SD and vicinity...
An expansive upper ridge will remain anchored over much of the
southwest and central CONUS through the period. Very hot
temperatures are expected this afternoon from MT into the Dakotas.
Isolated to scattered storms within the hot and well-mixed
environment will result in a broad area of at least isolated
severe-wind potential. 5% wind probabilities have been expanded to
cover this potential, with 15% wind probabilities (equivalent to
categorical Level 2/Slight Risk) added across parts of MT and SD,
where terrain features may enhance storm coverage within the
favorable severe-wind environment.

For parts of western/central MT, convection that develops by
early/mid afternoon near the high terrain is expected to spread
eastward into the hot and well-mixed environment. This convection
may be aided by a low-amplitude midlevel vorticity maximum moving
around the periphery of the upper ridge. Increasing storm coverage
and gradually strengthening mid/upper-level flow may allow for one
or more outflow-driven clusters to develop and spread
east-northeastward into early evening, with a threat of severe
gusts. Localized gusts of 75+ mph cannot be ruled out, especially if
deeper convection is able to spread into areas where very deep
mixing and heating to near/above 100 F occurs prior to storm
arrival.

Farther east, very strong heating is expected across parts of
western/central SD, with temperatures in some areas potentially
rising to near/above 105 F. Low-level moisture will be relatively
sparse, but MLCAPE of near/above 1000 J/kg will be possible where
50s F dewpoints can be maintained within the well-mixed environment.
Initial storm development near the Black Hills will quickly become
outflow dominant as it spreads eastward, with an increasing threat
of severe gusts. Deep-layer shear will be somewhat favorable for
organized convection, and some guidance depicts development of a
persistent cluster or loosely organized MCS that moves eastward
across SD along a weak surface boundary. Should this occur, a
corridor of more organized severe-wind threat (with gusts
potentially near/above 75 mph) will be possible.

...Northern/eastern MN into WI and Upper MI...
Conditional severe potential remains evident across parts of the
Upper Midwest, though confidence regarding storm coverage and timing
remains very low within the weakly forced environment. Moderate to
strong destabilization is possible along/south of a surface front
that is forecast to extend from northeast ND into northern MN/WI by
late afternoon. Effective shear of 50+ kt will be more than
sufficient for storm organization, but most guidance remains rather
muted regarding potential for diurnal storm development. If storms
are able to develop during the afternoon or evening, then a threat
for hail, damaging wind, and possibly a tornado could evolve. Even
if diurnal storm development is limited, vigorous elevated storms
may evolve within a warm-advection regime near/north of the front
late tonight, which would pose a threat for hail and perhaps locally
damaging wind. Confidence remains too low to include more than
Level-1/Marginal Risk equivalent probabilities at this time.

...Northeast NV/northern UT into eastern ID...
Storm development is expected during the afternoon across parts of
northeast NV, along the western periphery of the upper ridge. These
storms will spread into adjacent parts of southeast ID and northwest
UT with time. Strong to locally severe gusts will be possible with
these storms as they move northeastward through a well-mixed
environment.

...South-central/southeast AZ...
High-based convection is again expected across southeast AZ during
the afternoon, with initial downburst potential. Modest enhancement
to easterly flow along the southern periphery of the upper ridge may
allow for localized strong to severe gusts to spread westward into
parts of south-central AZ, before convection weakens later Saturday
night.

..Dean/Squitieri.. 07/25/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Sat Jul 25 12:50:36 2026

ACUS01 KWNS 251250
SWODY1
SPC AC 251248

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0748 AM CDT Sat Jul 25 2026

Valid 251300Z - 261200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS MONTANA AND
SOUTH DAKOTA...

...SUMMARY...
Storms with scattered severe wind gusts are possible across parts of
Montana and South Dakota this afternoon and evening.

...Montana to Dakotas...
A prominent upper ridge will persist over much of the
Southwest/central CONUS through tonight, with very hot temperatures
expected this afternoon from Montana into the Dakotas. Isolated to
scattered storms within the hot and well-mixed environment will
result in a broad area of at least isolated severe-wind potential.

For parts of western/central Montana, convection that develops by
early/mid afternoon near the high terrain is expected to spread
eastward. This convection may be aided by a low-amplitude mid-level
vort max moving around the periphery of the upper ridge. Increasing
storm coverage and gradually strengthening mid/upper-level flow may
allow for one or more outflow-driven clusters to develop and spread east-northeastward into early evening, with a threat of severe wind
gusts. Localized gusts of 75+ mph cannot be ruled out, especially if
deeper convection is able to spread into areas where very deep
mixing and heating to near/above 100 F occurs prior to storm
arrival.

Farther east, very strong heating is expected across parts of
western/central South Dakota, with temperatures in some areas
potentially rising to near/above 105 F. Low-level moisture will be
relatively sparse, but MLCAPE of near/above 1000 J/kg will be
possible where 50s F dewpoints can be maintained within the
well-mixed environment. Initial storm development near the Black
Hills will quickly become outflow dominant as it spreads eastward,
with an increasing threat of severe gusts as storms tend to increase
and potentially modestly organize as outflows aggregate. Some
guidance depicts development of a persistent cluster or loosely
organized MCS that moves eastward across South Dakota along a weak
surface boundary. Should this occur, a corridor of more organized
severe-wind threat (with gusts potentially near/above 75 mph) will
be possible this evening.

...Upper Midwest/Upper Great Lakes...
Conditional severe potential exists across parts of the Upper
Midwest spanning Minnesota to Upper Michigan, although confidence
regarding storm coverage and timing remains very low within the
weakly forced environment characterized by generally rising upper
heights. As morning stratus thins/erodes, moderate to strong
destabilization is possible along/south of a surface front
that is forecast to extend from northeast North Dakota into northern Minnesota/Wisconsin by late afternoon.

Impressively long hodographs with effective shear of 50+ kt will be
more than sufficient for storm organization, but most guidance
remains rather muted regarding potential for diurnal storm
development. If storms are able to develop during the afternoon or
evening, then a threat for hail, damaging wind, and possibly a
tornado could evolve. Even if diurnal storm development is limited,
at least isolated vigorous elevated storms may evolve within a
warm-advection regime near/north of the front late tonight, which
would pose a threat for hail and perhaps locally damaging wind.

...Northeast Nevada/northern Utah/eastern Idaho...
Storm development is expected during the afternoon across parts of
northeast Nevada, along the western periphery of the upper ridge.
These storms will spread into adjacent parts of southeast Idaho and
northwest Utah with time. Strong to locally severe wind gusts will
be possible with these storms as they move northeastward within a
well-mixed environment.

...South-central/southeast Arizona...
High-based convection is again expected across southeast Arizona
during the afternoon, with initial downburst potential. A modest
enhancement to easterly flow along the southern periphery of the
upper ridge may allow for localized strong to severe wind gusts to
spread westward into parts of south-central Arizona, before
convection weakens tonight.

..Guyer/Wendt.. 07/25/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Sat Jul 25 16:39:46 2026

ACUS01 KWNS 251639
SWODY1
SPC AC 251637

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1137 AM CDT Sat Jul 25 2026

Valid 251630Z - 261200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR CENTRAL
INTO EASTERN SOUTH DAKOTA...

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN CENTRAL AND
EASTERN MONTANA...

...SUMMARY...
Widespread severe gusts are possible across South Dakota late this
afternoon through the evening.

...SD into adjacent parts of IA/MN...
A prominent upper ridge centered over the central/southern Rockies
will feature the southern periphery of appreciably strong mid to
high-level flow extending from the Pacific Northwest across the
northern High Plains and into the north-central states. Late
morning surface analysis shows very hot temperatures ensuing across
western NE into the western half of SD with richer moisture (surface
dewpoints in the lower to mid 70s F) located over the eastern half
of NE/SD. Visible-satellite imagery shows some mid to high clouds
across northern WY moving towards the Black Hills. This patch of
clouds appears associated with a weak disturbance forecast to move
into western SD later this afternoon.

Downstream across SD, forecast soundings show very steep surface to
500-mb lapse rates developing as temperatures rise into the 100s F.
Expecting initially isolated to widely scattered storms to develop
near the Black Hills, as convective temperatures are breached.
Models show the gradual development of a cluster moving east across
SD early this evening. Have increased severe-wind probabilities to
account for observational and model-based trends towards an MCS
capable of peak gusts in the 75-90 mph range. This activity will
probably slowly weaken towards the MN/IA/SD border but perhaps
continue into early overnight with a wind threat.

...MT...
Isolated to scattered storms will likely form near the higher
terrain of southern MT later this afternoon with a gradual increase
in storm coverage as this moves east during the early evening. A
hot and well-mixed boundary layer will support severe gusts with the
stronger cores and associated outflow. There is some indication
this activity will cluster and potentially reach parts of
eastern/southeast MT by the late evening.

...Upper Midwest/Upper Great Lakes...
Conditional severe potential exists across parts of the Upper
Midwest spanning Minnesota to Upper Michigan into Wisconsin. Models
continue to show low storm chances as mid-level heights rise through
the late evening. Nonetheless, appreciable heating of a seasonably
moist boundary layer will result in strong potential buoyancy later
today into tonight. Elongated hodographs will support organized
storms capable of a wind/hail threat. Given a muted diurnal storm
signal in models, the greater chance for isolated storms appears to
be associated with warm advection activity late tonight.

...Northeast NV/northern UT/eastern ID...
Storm development is expected during the afternoon across parts of
northeast Nevada, along the western periphery of the upper ridge.
These storms will spread into adjacent parts of southeast Idaho and
northwest Utah with time. Isolated severe gusts may accompany the
stronger downdrafts.

...South-central/southeast AZ...
High-based convection is again expected across southeast Arizona
during the afternoon, with initial downburst potential. A modest
enhancement to easterly flow along the southern periphery of the
upper ridge may allow for localized strong to severe wind gusts to
spread westward into parts of south-central Arizona, before
convection weakens tonight.

..Smith/Moore.. 07/25/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Sat Jul 25 20:02:48 2026

ACUS01 KWNS 252002
SWODY1
SPC AC 252000

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0300 PM CDT Sat Jul 25 2026

Valid 252000Z - 261200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS CENTRAL
AND EASTERN SOUTH DAKOTA...INTO SOUTHWESTER MINNESOTA AND NORTHWEST
IOWA...

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF
CENTRAL MONTANA...

...SUMMARY...
Widespread severe gusts are possible across South Dakota late this
afternoon and into portions of southwestern Minnesota and northwest
Iowa through the evening.

...20 Update Northern Plains/Midwest...
Confidence continues to increase in widespread severe gusts
developing across parts of central and eastern SD late this
afternoon and into the evening. Very hot surface temperatures
(100-110F) are supporting very steep-low and mid-level lapse rates
of 8-9 C/km over western SD. Initial storms developing now with
temperature-dew point spreads of 40-50 F will favor efficient
outflow generation and an increasing potential for severe gusts as
convection develops and intensifies this afternoon.

The primary severe concern across the northern Plains and Midwest
remains the potential for widespread severe wind gusts with one or
more organized convective clusters. A CIG-2 wind area was added for
the potential for some peak gusts in the 80-100 mph range. Some
recent CAM guidance has trended toward more clustering and a compact
bowing cluster across central and eastern SD late this afternoon and
evening. A brief mesovortex tornado or two may also occur if a
bowing cluster can develop over astern SD. However, weaker overall
synoptic forcing suggests overall lower confidence in how widespread
the most intense storms will be. See MCD#1729 for short-term
information.

Downstream, wind probabilities and CIG-1 have been expanded along a
surface wind shift/buoyancy gradient into parts of northeast NE, IA
and southern MN. Recent HRRR/RRFS time-lagged runs continue to show
a strong cluster moving east and then southeastward this evening and
into the overnight hours. Strong to severe gusts will remain
possible with these storms given the large buoyancy.

Farther north across MN, isolated storms, including supercell
structures could support isolated hail or damaging gusts this
evening.

...MT...
Scattered to widespread high-based storms remain likely this
afternoon and evening over central and southern MT. Steep-lapse
rates in the lowest 3-5 km will support a risk for severe gusts.
Some clustering may occur as storms spread eastward into this
evening. No changes were made to the outlook, see the prior
discussion.

..Lyons.. 07/25/2026

.PREV DISCUSSION... /ISSUED 1137 AM CDT Sat Jul 25 2026/

...SD into adjacent parts of IA/MN...
A prominent upper ridge centered over the central/southern Rockies
will feature the southern periphery of appreciably strong mid to
high-level flow extending from the Pacific Northwest across the
northern High Plains and into the north-central states. Late
morning surface analysis shows very hot temperatures ensuing across
western NE into the western half of SD with richer moisture (surface
dewpoints in the lower to mid 70s F) located over the eastern half
of NE/SD. Visible-satellite imagery shows some mid to high clouds
across northern WY moving towards the Black Hills. This patch of
clouds appears associated with a weak disturbance forecast to move
into western SD later this afternoon.

Downstream across SD, forecast soundings show very steep surface to
500-mb lapse rates developing as temperatures rise into the 100s F.
Expecting initially isolated to widely scattered storms to develop
near the Black Hills, as convective temperatures are breached.
Models show the gradual development of a cluster moving east across
SD early this evening. Have increased severe-wind probabilities to
account for observational and model-based trends towards an MCS
capable of peak gusts in the 75-90 mph range. This activity will
probably slowly weaken towards the MN/IA/SD border but perhaps
continue into early overnight with a wind threat.

...MT...
Isolated to scattered storms will likely form near the higher
terrain of southern MT later this afternoon with a gradual increase
in storm coverage as this moves east during the early evening. A
hot and well-mixed boundary layer will support severe gusts with the
stronger cores and associated outflow. There is some indication
this activity will cluster and potentially reach parts of
eastern/southeast MT by the late evening.

...Upper Midwest/Upper Great Lakes...
Conditional severe potential exists across parts of the Upper
Midwest spanning Minnesota to Upper Michigan into Wisconsin. Models
continue to show low storm chances as mid-level heights rise through
the late evening. Nonetheless, appreciable heating of a seasonably
moist boundary layer will result in strong potential buoyancy later
today into tonight. Elongated hodographs will support organized
storms capable of a wind/hail threat. Given a muted diurnal storm
signal in models, the greater chance for isolated storms appears to
be associated with warm advection activity late tonight.

...Northeast NV/northern UT/eastern ID...
Storm development is expected during the afternoon across parts of
northeast Nevada, along the western periphery of the upper ridge.
These storms will spread into adjacent parts of southeast Idaho and
northwest Utah with time. Isolated severe gusts may accompany the
stronger downdrafts.

...South-central/southeast AZ...
High-based convection is again expected across southeast Arizona
during the afternoon, with initial downburst potential. A modest
enhancement to easterly flow along the southern periphery of the
upper ridge may allow for localized strong to severe wind gusts to
spread westward into parts of south-central Arizona, before
convection weakens tonight.

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

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