AWUS01 KWNH 132142
FFGMPD
MIZ000-WIZ000-MNZ000-IAZ000-140330-

Mesoscale Precipitation Discussion 0100
NWS Weather Prediction Center College Park MD
541 PM EDT Mon Apr 13 2026

Areas affected...Much of Wisconsin, Southeastern Minnesota, and
U.P. of Michigan

Concerning...Heavy rainfall...Flash flooding likely

Valid 132140Z - 140330Z

SUMMARY...Thunderstorms forming along a warm frontal boundary will
organize into training lines of storms, over an area of saturated
soils through this evening. Flash flooding likely.

DISCUSSION... Several areas of convection have begun to form along
a warm frontal boundary across much of Wisconsin and southeast
Minnesota this afternoon. These storms are being fed by moisture
influx with PWATs around 1 inch along the front, but over 1.3
inches along the Illinois/Wisconsin border, based on the latest
SPC Mesoanalysis. CAMs guidance is in good agreement that the
storms will continue to grow upscale into an MCS that will then
support training storms propagating eastward across central and
northern Wisconsin. A cold front shown across northern Minnesota
will press southeastward and eventually help to push the MCS
southward with time.

Soils across Minnesota and Wisconsin are nearly saturated due to
recent rainfall and around the U.P. of Michigan, recent snowmelt
as shown on NASA SPoRT imagery. With above average river levels
and nearly saturated soils across nearly all of Wisconsin, almost
all of the rainfall expected from this forecast MCS will convert
to runoff quickly. FFGs across this region on average are around
1.5 inches/1 hour, 2 inches/3 hours, and 2.5 inches/6 hours. These
values are likely to be exceeded with multiple rounds of training
storms expected late this afternoon and this evening. The cells
south of the Twin Cities have a history of rainfall rates
exceeding 2 inches/hour at times, showing that the atmosphere is
capable of rates exceeding these aforementioned FFG values.

Wegman

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!7G1XSLTDBBKEgE6KnC6HjiSFk-T-6U4Bgr0ABoBXm8-JrDZHBYlj134353NlsdE9nf1H= lWiBku11TKmoojCTL9tJ1SM$ for graphic product...

ATTN...WFO...ARX...DLH...GRB...MKX...MPX...MQT...

ATTN...RFC...MSR...NWC...

LAT...LON 46828894 46588739 45458680 44468747 43548763=20
43368904 43429003 43509140 43739228 44039312=20
44719364 45179376 45829361 46349312 46619141=20 =20=20=20=20=20=20=20=20=20=20=20=20

=3D =3D =3D
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AWUS01 KWNH 132331
FFGMPD
MNZ000-IAZ000-SDZ000-140330-

Mesoscale Precipitation Discussion 0101
NWS Weather Prediction Center College Park MD
730 PM EDT Mon Apr 13 2026

Areas affected...Southwest Minnesota and Northwest Iowa

Concerning...Heavy rainfall...Flash flooding possible

Valid 132330Z - 140330Z

SUMMARY... Clusters of storms are forming across portions of
southwest Minnesota and northwest Iowa this evening. Localized
rain rates to 2" per hour could cause isolated to widely scattered
instances of flash flooding.

DISCUSSION... Convective coverage has rapidly increased across
portions of southwest Minnesota and northwest Iowa this evening as
part of a broader low pressure center and warm frontal system,
tapping into Gulf moisture riding up to the south and east of
these features. Rainfall rates of up to 2 inches per hour have
been observed on radar, with somewhat moistened soils in the area
from recent rainfall, based on NASA SPoRT imagery.

CAMs guidance is in poor agreement in this area, with none of the
guidance suggesting convective coverage would be as robust in this
area than has already formed. For those that have a hint of the
southern extent of this convection (NAMnest, ARW to a lesser
extent, and HRRR to an even lesser extent), all suggest much
faster and more eastward motions to these storms than have already
been occurring. Thus, with slower and more northward storm
motions, towards areas where storms have already formed across far
southern Minnesota, expect more robust training and heavier
rainfall rates than the guidance is suggesting, favoring more
potential for flash flooding over the next few hours.

Wegman

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!6X1tqeZU-LUfkuQOxQe1ZCk91388CwJGlSqrn-Xsd_p7IlWiLuBHXrVEhhbbR6vhNbAj= BNCnIg_odYgJqLuN6203qEk$ for graphic product...

ATTN...WFO...ARX...DMX...FSD...MPX...

ATTN...RFC...KRF...MSR...NWC...

LAT...LON 45369378 44999377 44649360 44179331 43929301=20
43769257 43649215 43449216 43129229 42679296=20
42619447 42549518 42579577 42809622 43209651=20
43539693 44139664 44909551 45309470 45349421=20 =20=20=20=20=20=20=20=20=20=20=20=20

=3D =3D =3D
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AWUS01 KWNH 140347
FFGMPD
MIZ000-WIZ000-IAZ000-140800-

Mesoscale Precipitation Discussion 0102
NWS Weather Prediction Center College Park MD
1145 PM EDT Mon Apr 13 2026

Areas affected...southern WI into central/northern Lower MI

Concerning...Heavy rainfall...Flash flooding likely

Valid 140344Z - 140800Z

Summary...Areas of flash flooding will be likely from southern WI
into central/northern Lower MI over the next 4-5 hours. Saturated
to nearly saturated soils are expected to be a contributing factor
to excess runoff from rainfall rates of 1-2 in/hr.

Discussion...0320Z radar imagery across the Upper Midwest showed
an MCS with an elongated convective line on its southern flank,
oriented west-east from the MN/WI/IA tri-state region into
northwestern Lower MI. The cluster of thunderstorms were located
along a quasi-stationary front that extended west to east through
central WI/MI with 500-2000 J/kg MLCAPE (highest over northeastern
IA, lowest over Lower MI) estimated just south of the boundary per
03Z SPC mesoanalysis data. Infrared imagery showed cloud tops
continued to cool with divergence aloft aided within the
right-entrance region of a 110-130 kt upper level jet streak
positioned over Lake Superior into southern Quebec. 850 mb VAD
wind data showed 50-60 kt of SSW flow from eastern IA into
northern IL and southern WI, aiding rapid moisture transport
across Lake Michigan into Lower MI with upstream moisture over the
Midwest between 1.2 and 1.4 inches.

As the main surface low along the front in northwestern IA
advances ENE tonight, continued southerly flow ahead of the low
into the ongoing complex of storms should sustain convection
within the unstable airmass for several more hours. Mean cell
motions from the W to SW will interact with the southerly low
level inflow allowing for segments of the line to advance
southeastward at times. Cell mergers and training within the
linear segments of the MCS will attain rainfall rates of 1-2 in/hr
at times with an overall movement toward the east through 08Z.
Most soils across the region are saturated due to snowmelt and/or
recent rainfall, with additional heavy rainfall more quickly
translating into runoff compared to average. Therefore, areas of
flash flooding are likely to occur across southern WI into Lower
MI over the next 4-5 hours.

Otto

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!7L1O-mnGFqvdnGQKawceVca5wKPKEE_53aZyZ3QByeXtRcHpH_iNlJdj0PPvcB--9qxe= 996tFkVy9okNckkMMmvxAfw$ for graphic product...

ATTN...WFO...APX...ARX...DTX...GRB...GRR...MKX...

ATTN...RFC...MSR...NWC...

LAT...LON 45818459 45288327 44528305 43748367 42798585=20
42498773 42528950 42719070 43409120 44019101=20
44319034 44578902 45028737 45468637=20

=3D =3D =3D
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AWUS01 KWNH 141802
FFGMPD
INZ000-WIZ000-ILZ000-MNZ000-IAZ000-150000-

Mesoscale Precipitation Discussion 0103
NWS Weather Prediction Center College Park MD
200 PM EDT Tue Apr 14 2026

Areas affected...Eastern IA...Southern WI...Northern and Eastern
IL...Western and Central IN

Concerning...Heavy rainfall...Flash flooding possible

Valid 141800Z - 150000Z

SUMMARY...Developing and expanding clusters of heavy showers and
thunderstorms coupled with locally wet/sensitive antecedent
conditions will foster an isolated to scattered threat for flash
flooding going through early this evening.

DISCUSSION...Early afternoon GOES-E visible satellite imagery
shows stronger diurnal heating promoting a steady destabilization
of the boundary layer across eastern IA, western IL and nosing
into southwest WI. This airmass is pooling south and east of a
quasi-stationary front as multiple waves of low pressure advance
along it.

Some modest CINH remains in place across these areas, but MLCAPE
values of 2000 to 3000 J/kg are already in place, and this is
being supported by steep mid-level lapse rates transiting the
Midwest. Meanwhile, satellite imagery shows a modest mid-level
shortwave impulse ejecting northeastward across central and
eastern IA down through northern MO and into western IL. This
energy coupled with additional solar insolation should erode the
remaining CAP across the region and set the stage for convective
initiation. Much of this should be focused in close proximity to a leftover/diffuse outflow boundary from the early-day convection.

As convection grows upscale, there will gradually be concerns for
a few cell-mergers and some cell-training. A combination of
multicells and supercells will be likely given the strong
instability in conjunction with strong shear (effective bulk shear
approaching 50 kts). The larger scale environment is also
increasingly moist with aid from a southwest low-level jet of 30
to 40+ kts. Deeper layer southwesterly moisture transport is noted
aloft too with elevated CIRA-LVT magnitudes.

Locally significant model disagreement is noted through this
evening with the placement of the convection and its general
evolution, but a multi-model consensus suggests eastern IA,
northern IL and southern WI seeing one focus for convection, with
areas of central/eastern IL and into western IN seeing a second
focus.

Rainfall rates will be capable of reaching 1 to 2 inches/hour,
with some localized totals by early this evening of 2 to 4 inches.
The antecedent conditions are locally quite sensitive, and
especially from eastern IA through northern IL and southern WI.
Isolated to scattered areas of flash flooding will be possible as
a result.

Orrison

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!6rVoRhS9MtZ95Sj6aCH05vO57EMIhqP-DU7yZfIuOyX3spDEUeEb69FAjBiqp3DRaLHv= v5fBXogv1SsUKymmwi2Cj7Y$ for graphic product...

ATTN...WFO...ARX...DMX...DVN...ILX...IND...IWX...LOT...MKX...

ATTN...RFC...MSR...TIR...NWC...

LAT...LON 43969015 43808891 43378810 42458766 41648679=20
41038574 40368523 39538567 39238682 39538845=20
40048943 41199043 41619249 41909331 42369330=20
42689297 43329238 43909121=20

=3D =3D =3D
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AWUS01 KWNH 142204
FFGMPD
TXZ000-OKZ000-150402-

Mesoscale Precipitation Discussion 0104
NWS Weather Prediction Center College Park MD
603 PM EDT Tue Apr 14 2026

Areas affected...portions of western North Texas and the
southeastern Texas Plains into southern and central Oklahoma

Concerning...Heavy rainfall...Flash flooding possible

Valid 142202Z - 150402Z

Summary...Ongoing convective evolution suggests an increasing
flash flood threat for areas near Vernon, Lawton, and eventually
toward the I-35 corridor in central Oklahoma through 04Z/11p
Central.

Discussion...Scattered, deep convection continues to increase in
coverage across western north Texas and southwestern Oklahoma.=20
Recent surface obs indicate subtle veering of flow west of a
dryline across the Texas South Plains, and objective
analyses/satellite suggest subtle vort maxima riding atop the
dryline and over a warm, unstable airmass over the discussion
area. These trends suggest continued expansion of convective
coverage across the discussion area over the next few hours
(especially as the low-level jet ramps up), with areas of training
and mergers expected to foster spots of 1-2.5 inch/hr rain rates
especially near the Red River.

Antecedent conditions are a somewhat moist across the region from
prior heavy-rain events over the past week. Sensitive terrain and
urbanized areas (near Lawton in particular) could also experience
a higher runoff risk. The overall focus for flash flooding should
revolve around sensitive spots and locations of cell mergers -
with background/mean flow fields (around 35-45 knots) suggestive
that prolonged heavier rainfall (and >1.5 inch/hr rates/local FFG)
may not occur on a widespread basis.

Flash flooding is possible with this regime initially over
southwestern OK and western north Texas, with the risk spreading
northeastward toward I-35 in Oklahoma later tonight.

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!6VoGB_M1a_9ytYeE6UWe8iLQ051eCBJO1BKLKOA725_8XkZLNT0flAJJgr3NBTOQttOi= 3Q_C8zlaihqgqTHhLhv-AsE$ for graphic product...

ATTN...WFO...AMA...FWD...LUB...OUN...SJT...TSA...

ATTN...RFC...FWR...TUA...NWC...

LAT...LON 35969737 35969640 34589601 33539662 33169844=20
32870002 32960060 33570089 34530062 35180008=20
35599891=20

=3D =3D =3D
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AWUS01 KWNH 142357
FFGMPD
MIZ000-WIZ000-ILZ000-150556-

Mesoscale Precipitation Discussion 0105
NWS Weather Prediction Center College Park MD
756 PM EDT Tue Apr 14 2026

Areas affected...portions of Wisconsin and Michigan

Concerning...Heavy rainfall...Flash flooding likely

Valid 142356Z - 150556Z

Summary...Deep convection will continue to produce heavy rainfall
while migrating eastward through Wisconsin, across Lake Michigan,
and eventually into Lower Michigan. Flash flooding is likely
given ongoing impacts and local sensitivities in the region.

Discussion...Deep convection has evolved as expected from the
Mississippi River eastward across much of Wisconsin and
northeastern Iowa. Favorable interactions with a warm frontal
zone and steep lapse rates aloft have enabled intense updrafts and
embedded mesocyclones to occasionally merge and produce spots of 2
inches/hr of rainfall at times. Areas of flash flooding are
possible in the short term.

Of particular concern is the potential for storms to expand
northeastward and eastward in coverage. The position of warm
frontal zone over central Wisconsin and cooler Lake Michigan
waters may weaken convection as storms move atop slightly
cooler/stable low-level air, although very steep lapse rates aloft
downstream should maintain convection as it migrates toward areas
that have experienced 3-5 inches of rainfall over the past 3 days,
with ongoing impacts to local watersheds in the area. FFGs fall
to below 1 inch/hr in a few downstream areas, highlighting the
sensitivity of the ground conditions there. Approaching heavy
rainfall may worsen ongoing recovery efforts and perhaps cause new
instances of flash flooding to occur.

Peak flash flood potential will spread into northeastern Wisconsin
in the 00-04Z timeframe and eventually spread into Lower Michigan
generally from 02Z onward.

Cook

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!7kgjJfhxvhUeO4YT74P3s8DQ6l_xpQ24IGlUfxoboD8Y2QG0QSY5486_Dp46h_RYXL9-= Huhx9HqLAuI5qFzRolT1pZE$ for graphic product...

ATTN...WFO...APX...ARX...DTX...DVN...GRB...GRR...IWX...LOT...
MKX...MQT...

ATTN...RFC...MSR...TIR...NWC...

LAT...LON 45408569 45298379 44028325 42218366 41788510=20
41898733 42518836 42508976 43319091 44929033=20
45348892=20

=3D =3D =3D
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AWUS01 KWNH 150024
FFGMPD
INZ000-WIZ000-ILZ000-IAZ000-150623-

Mesoscale Precipitation Discussion 0106
NWS Weather Prediction Center College Park MD
824 PM EDT Tue Apr 14 2026

Areas affected...eastern Iowa, northern Illinois, southern
Wisconsin

Concerning...Heavy rainfall...Flash flooding likely

Valid 150023Z - 150623Z

Summary...Thunderstorms are expected to not only persist, but
train and repeat over areas very near the WI/IL border vicinity
over the next several hours. Flash flooding is likely, and
significant impacts cannot be ruled out.

Discussion...Radar mosaic imagery depicts a mature convective
complex with embedded linear structures and mesocyclones extending
from south-central WI (near Madison) southwestward to near Dubuque
and Cedar Rapids. Other convection was anchored/backbuilding near
a warm front close to and just north of Milwaukee. Each of these
convective clusters were producing expanding cold pools that were
progressively orienting perpendicular to increasing southwesterly
low-level flow, with 45kts now noted on mesoanalyses at 850mb
across much of IA/IL. Latest indications are that these
convective clusters will continue to backbuild and train owing to
convergence along strengthening outflows and strong upstream
buoyancy (~3000 J/kg MLCAPE).=20

The scenario is beginning to favor multiple hours of repeating
convection (1-2.5 inch/hr rain rates) very close to where ongoing
convection exists currently. Localized 3-5 inch rainfall totals
are possible over the next 6 hours. This could result in
significant flash flood potential as FFG thresholds across the
area are only at around 1 inch/hr and will be readily exceeded.=20
This potential will likely exist through 06Z/1a central, with
populated areas near Madison, Milwaukee, Rockford, and perhaps
Chicago potentially experiencing impacts.

Cook

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!_RimPN4452Lz3CSs_IelT7ml5jPYxQHeJmRoaCJABg12dpxpwKNOMVjDMdImE2PL8K-g= NjzLo2BW4jUzEE5JhCUattE$ for graphic product...

ATTN...WFO...ARX...DMX...DVN...LOT...MKX...

ATTN...RFC...MSR...NWC...

LAT...LON 43498958 43368824 42998765 41958741 41538758=20
41248859 41319028 41369158 41559227 41839253=20
42249259 43009239 43179125=20

=3D =3D =3D
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AWUS01 KWNH 150528
FFGMPD
OHZ000-MIZ000-INZ000-WIZ000-ILZ000-151020-

Mesoscale Precipitation Discussion 0107
NWS Weather Prediction Center College Park MD
127 AM EDT Wed Apr 15 2026

Areas affected...northeastern IL/southeastern WI to southern
MI/northern IN

Concerning...Heavy rainfall...Flash flooding possible

Valid 150526Z - 151020Z

SUMMARY...Scattered flash flooding will be possible in the
vicinity of the eastern IL/WI border, eastward to southern Lower
MI, northern IN and northwestern OH. Rainfall rates of 1-2 in/hr
(locally higher) are expected along with peak additional rainfall
totals of 2-3 inches through 10Z

DISCUSSION...05Z radar imagery depicted a trailing stratiform MCS
moving across Lower MI with the leading edge pressing
southeastward across southern MI into northern IN. An outflow
boundary was analyzed ahead of the convective line from
southeastern MI into northern IN/IL with upstream thunderstorm
development occurring north of the western portion of the boundary
along the WI/IL border. 925-850 mb winds were from the SW at 45-55
kt to the south of the boundary over north-central IL and
1000-2000 J/kg MLCAPE extended from the MI/IN border back west to
the MS River, per SPC mesoanalysis data.

The leading edge of the MCS is expected to continue tracking
toward the ESE across southeastern MI into northern IN and
northwestern OH over the next 1 to 2 hours, but back to the west,
continued convective development is likely as moist, low level
flow overruns the slow moving western portion of the rain-cooled
outflow. Mean cell motions are generally from the west which will
setup a favorable pattern for training from west to east given
alignment with the low level boundary. Rainfall rates of 1 to 2
in/hr are likely (locally higher possible), and an additional 2 to
3 inches of rain is expected through 10Z where cell training is
maximized. Flash flood guidance is less than 2 inches in 3 hours
for some locations, especially across northern IL/southern WI
where heavy rain over the past 12-24 hours has contributed to
reduced soil infiltration.

Otto

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!4gUZnv0Qxp7R8HWlZNMdEUOjnXzvwcsKhaQiAxAI-iAuF1r4A3I0uJ-ZiXaLC7iOJvba= 8vQFf0NVtX6daqnhMsw5PxE$ for graphic product...

ATTN...WFO...CLE...DTX...GRR...IWX...LOT...MKX...

ATTN...RFC...MSR...TIR...NWC...

LAT...LON 43668276 43568226 43138209 42448225 41578312=20
41298455 41268640 41468819 41788922 42428939=20
42908878 42848652 42988484 43578350=20

=3D =3D =3D
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AWUS01 KWNH 152148
FFGMPD
WIZ000-ILZ000-IAZ000-160246-

Mesoscale Precipitation Discussion 0108
NWS Weather Prediction Center College Park MD
547 PM EDT Wed Apr 15 2026

Areas affected...southern Wisconsin, northern Illinois

Concerning...Heavy rainfall...Flash flooding likely

Valid 152146Z - 160246Z

Summary...Thunderstorms will migrate eastward across wet/sensitive
areas from yesterday's rainfall especially across Wisconsin.=20
Flash flooding is likely.

Discussion...Scattered thunderstorms have organized along a
frontal boundary from just north of Dubuque to Des Moines. The
storms are exhibiting linear organization so far in their
evolution, with forward propagation and 40-50 kt speeds generally
limiting their rainfall potential to around 1 inch/hr or less.=20
Flash flooding is possible on an isolated basis in the short term.

Over the next 1-4 hours, however, storms will migrate eastward
along a remnant outflow/frontal boundary extending east-west
across southern Wisconsin (generally from Sheboygan to Wisconsin
Dells). As low-level flow increases over Illinois, convergence
along this boundary could result in additional convection
developing in southern/southeastern Wisconsin out ahead of the
ongoing quasi-linear complex. This will increase potential for training/mergers and prolonged rainfall rates in areas that have
already experienced 1-4 inches of rainfall yesterday near/north
and west of Milwaukee and across far northern Illinois. FFGs are
less than 1 inch/hr in some spots and could readily be exceeded
where mergers take place. Flash flooding is likely - especially
in sensitive areas that received rainfall/runoff issues late
yesterday and early today.

Cook

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!5opxEbcOifoi00puOb7C5zg01c-pm_jWC9NSJEfq1mEfdNRUZ1jcte1ysb-WmCRTq14u= t29w5aSU3WiQJFXPtvtydIo$ for graphic product...

ATTN...WFO...ARX...DVN...GRB...LOT...MKX...

ATTN...RFC...MSR...NWC...

LAT...LON 44558947 44408783 43208786 42008773 41548866=20
41449051 42319153 43979095=20

=3D =3D =3D
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AWUS01 KWNH 152301
FFGMPD
ILZ000-MOZ000-OKZ000-KSZ000-160459-

Mesoscale Precipitation Discussion 0109
NWS Weather Prediction Center College Park MD
700 PM EDT Wed Apr 15 2026

Areas affected...much of Missouri, a small part of southeastern
Kansas

Concerning...Heavy rainfall...Flash flooding possible

Valid 152259Z - 160459Z

Summary...Deep convection is organizing into clusters/segments
with localized training. Localized flash flooding is possible
especially in low-spots and sensitive areas.

Discussion...Convection continues to mature along and east of a
dryline extending from near Kansas City south-southwestward to
near Bartlesville and Oklahoma City, Oklahoma. The storms are in
a very moist, unstable airmass (with 2000 J/kg SBCAPE and 1.5 inch
PW values) supporting locally heavy rainfall at times despite
appreciable storm motions of around 30-40 knots.

The storms are in an environment with modest forcing for ascent
due to the slow movement of the dryline, with an approaching
vort-max over Nebraska and confluence ahead of the dryline helping
to deepen and expand convective coverage. Because storms aren't
strictly confined to the dryline, a few areas of training have
been noted (especially across far southwestern Missouri near
Joplin). These trends should continue for several more hours as
evidence of any distinct upscale growth into forward-propagating
linear segments (that would effectively reduce rain rates) is
currently unclear.

Localized training/repeating is likely to result in spots of 1-2
inch/hr rain rates at times on a localized basis. These rain
rates will threaten local FFG thresholds, with local sensitivities
also contributing to a potential flash flood risk. This risk will
persist for several hours this evening - perhaps through 03-04Z
tonight.

Cook

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!4QBPUYiOvvcrSPYpuhtkEviwBvLAooHGfmdwrtbeqZBMskhBe_do-t8cvF3LxHUIUCMe= m9tMCSe9Cl1O5RzzcsdF2es$ for graphic product...

ATTN...WFO...DVN...EAX...ICT...LSX...PAH...SGF...TSA...

ATTN...RFC...KRF...MSR...ORN...TUA...NWC...

LAT...LON 40509182 39399086 37999060 37039114 36699282=20
36749448 37119532 38149503 39479452 40199364=20 =20=20=20=20=20=20=20=20=20=20=20=20

=3D =3D =3D
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AWUS01 KWNH 160012
FFGMPD
ARZ000-TXZ000-OKZ000-160609-

Mesoscale Precipitation Discussion 0110
NWS Weather Prediction Center College Park MD
810 PM EDT Wed Apr 15 2026

Areas affected...southern/southeastern Oklahoma, far north Texas,
far western Arkansas

Concerning...Heavy rainfall...Flash flooding possible

Valid 160009Z - 160609Z

Summary...An axis of training convection has materialized from
near Wichita Falls through Ardmore to near McAlister. This heavy
rain axis should translate east-northeastward over the next few
hours, with flash flooding possible especially across southern
Oklahoma.

Discussion...Initial scattered convection has recently aligned
into a focused, training axis of cells along the Red River Valley
this evening. The storms are in a weakly forced environment, with
forcing for ascent resulting from the glancing influence of a
mid-level wave over Nebraska and weakly confluent low-level flow
across the region. The orientation of cells parallel to mean flow
aloft - combined with their gradual maturity and establishment of
cold pools - suggests that training convection will continue to be
an issue for at least a few hours. This training band of
convection will gradually translate east-northeastward into more
of eastern Oklahoma and perhaps far western Arkansas through the
overnight hours. A secondary training band of convection
near/north of the Dallas/Fort Worth metroplex may also materialize
over the next couple hours.

Ground conditions are relatively dry in many areas, with hourly
FFG thresholds exceeding 2-2.5 inches in spots. This suggests
isolated flash flood potential across the region - mainly tied to
low spots and/or urban areas. Persistence of training, however
(as evidenced by 2-2.5 inch/hr rain rates near Ardmore) suggests
that appreciable impacts may occur where rainfall is heaviest and
most persistent. This isolated flash flood threat should persist
for several hours - perhaps through 06Z/1a central.

Cook=20

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!94K4h8YfYfUxaStsHe_mwQL2Cg4STxUAwOgtVe0vJgX8kBrY3h64uUeSF04aU6SgfTz9= sW5g0eOrXgiqZql0yM0HAKo$ for graphic product...

ATTN...WFO...FWD...LZK...OUN...SHV...TSA...

ATTN...RFC...FWR...ORN...TUA...NWC...

LAT...LON 35899509 35869426 34929421 33509505 33079635=20
32859832 34239831 35069740=20

=3D =3D =3D
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AWUS01 KWNH 160234
FFGMPD
MIZ000-INZ000-WIZ000-ILZ000-160800-

Mesoscale Precipitation Discussion 0111
NWS Weather Prediction Center College Park MD
1033 PM EDT Wed Apr 15 2026

Areas affected...Northern IL...Far Southeast WI...Southern L.P. of
MI...Far Northwest IND...

Concerning...Heavy rainfall...Flash flooding likely

Valid 160235Z - 160800Z

SUMMARY...Potential for localized flash flooding continues through
the early overnight period; though coverage should become more
scattered with loss of heating/rainfall intensity. Rates of
1.5-1.75"/hr and spots of 2-3" remain possible.

DISCUSSION...Regional RADAR depicts a mature MCV across central
Lake Michigan just east of Milwaukee progressing toward
Holland/Muskegon, MI with a trailing QLCS convective line
extending across SE WI into the NW Exurbs of Chicago along W I-88
in N IL toward the Quad Cities. The cold pool appears to be
maturing as well, increasing forward propagation of the line
particularly through the middle, toward the WI/IL line, this is
reducing overall residency time for extreme rainfall totals, but
the short-term heavy bursts may still result in 1-1.5" in 30 to 60
minutes. Given recent heavy rainfall and saturated upper soil
profiles and proximity to hydrophobic urban conditions near
Chicago will result in increased run-off and likely incidents of
localized flash flooding/rapid rise flood, especially in the next
few hours.

GOES-WV shows expanding divergence region along the entrance of a
100 kt 3H speed max across the LP of MI at this time, helping to
maintain the MCV crossing the more stable air of Lake Michigan but
solid southwesterly warm-air advection is allowing for downstream
convergence with limited but sufficient MUCAPE of 500-750 J/kg.=20
VWP shows solid 850-700 40-45kt flow at the western nose of the
deep layer moisture axis where overall PW totals are increasing to
over 1.25". This will likely continue to support 1.5-1.75"/hr
rates and given the record wet spring across the SW LP; FFGs are
compromised in spots and while typically sandy and able to absorb
these rates and totals up to 2-3", saturation over 75% to 85% will
still quickly be overwhelmed with above normal run off and
potential for localized flash flooding conditions. However,
proximity to the unstable air will be increasing (along with
overall diurnal loss) and overall intensity of thunderstorms will
be steadily increasing through the night reducing overall coverage
and magnitude of flooding potential.

Gallina

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!4LPc5RRJ7D_EWUR-GQyFYstxacfepZIrau-Gq7EetmrgliaA_S5VAKvEdlNZqw0hlovq= memycrUKXrRQJ4-THjJqulI$ for graphic product...

ATTN...WFO...DTX...DVN...GRR...IWX...LOT...MKX...

ATTN...RFC...MSR...NWC...

LAT...LON 43868583 43758458 43508280 42468379 41648587=20
41268769 41238976 41499024 42108976 42648902=20
42968835 43578710=20

=3D =3D =3D
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AWUS01 KWNH 160311
FFGMPD
ILZ000-MOZ000-160800-

Mesoscale Precipitation Discussion 0112
NWS Weather Prediction Center College Park MD
1110 PM EDT Wed Apr 15 2026

Areas affected...Central Illinois...East-Central/Southeast
Missouri...

Concerning...Heavy rainfall...Flash flooding possible

Valid 160310Z - 160800Z

SUMMARY...Mature MCV continues to provide solid WAA ascent coupled
with nose of enhanced deep layer moisture likely to support
efficient rainfall production with rates of 1.5-1.75" and streaks
of 2-3" totals resulting in possible incident(s) of localized
flash flooding.

DISCUSSION...Regional RADAR suite depicts a maturing MCV just
southwest of metro St. Louis lifting northeastward at this time.=20
GOES-E WV and RADAR show a broadening mid-level baroclinic
leaf/shield indicative of continued favorable evacuation aloft to
maintain the MCS for the next few hours. VWP and RAP analysis
denote the broad divergence is supporting strengthening low level
flow with solid confluence at the nose of the deeper layer
moisture axis. CIRA LPW shows corridor of 850-500mb moisture is
aligned ideally with the southwesterly flow but sfc to 850mb
moisture is very broad and increasing to support TPW value in
excess of 1.5". The 30-35kts of 850-700mb confluent flow in this
moisture regime will support 1.5-1.75" rainfall production even
with reducing/narrowing unstable axis (generally 500-750 J/kg of
MUCAPEs). The MCV is also providing a corralling of downstream
flow into a well defined deformation axis that is generally
parallel to the deeper layer steering. This orientation will be
the supportive requirement for increased duration to support
localized steaks of 2-3" totals.

Unlike further north, the ground conditions are much drier due to
the prolonged drought. Yet, FFG values of 1.5-2"/hr and 2-3"/3hr
are in the realm of exceedance and while not all locations will be
exceeded there should be a few areas that may lead to localized
flash flooding conditions through the early overnight period. As
such, flash flooding is considered possible across central IL back
through east-central MO; with slightly higher potential in the
urban areas near Metro St. Louis, due to hydrophobic grounds and
drainage.=20

Gallina

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!_WoxM95G8ExX39lGSpA8s-H7qn-FUCdGbkYh4vn_8BhypuFWDWSIc__7RJp008JX_uhC= d3_AwawJzGwp-3qEB59Qe3Q$ for graphic product...

ATTN...WFO...ILX...LSX...PAH...SGF...

ATTN...RFC...KRF...MSR...ORN...TIR...NWC...

LAT...LON 40338843 39928763 39148773 38638840 37699014=20
37499135 37969181 38549157 38819130 39579024=20
40138941=20

=3D =3D =3D
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AWUS01 KWNH 160444
FFGMPD
MOZ000-ARZ000-OKZ000-KSZ000-160845-

Mesoscale Precipitation Discussion 0113
NWS Weather Prediction Center College Park MD
1243 AM EDT Thu Apr 16 2026

Areas affected...Northeast Oklahoma...Southwest Missouri...Adj.
Northwest Arkansas...

Concerning...Heavy rainfall...Flash flooding possible

Valid 160445Z - 160845Z

SUMMARY...A few more hours of potential localized flash flooding
due to slow moving/training thunderstorms across the Ozark Plateau.

DISCUSSION...GOES-E 10.3um IR and regional RADAR mosaic shows a
solid warming/weakening trend to the convective line across much
of the Ozark Plateau. RAP analysis shows warming low levels and
increasing CINH trends across the remaining well of 1000-2000 J/kg
of MLCAPE, the exception remaining along the upwind edge across NE
OK; and this is where the healthiest updrafts remain. Still,
KINX/KSGF show most are starting to have dominating outflow
patterns. However, as the dry-line retreated and the mean
upper-level shortwave trough across IA is kicking east; a weakness
in the overall mid-level flow/steering is lying perpendicular to
weakening but sufficient southerly surface to boundary layer/925mb
flow providing solid moisture flux convergence in proximity to the
remaining MLCAPE axis. Tds in the upper 60s to low 70s. With this
convergence and steering flow parallel to the boundary (and
slacking), training or increased downdraft residency may allow for
a narrow axis of enhanced rainfall rates up to 1.75"/hr for a
potential of localized 2-3" total. Beside naturally lower FFG
due to complex terrain across the Ozark Plateau, even further west
into NE OK, FFG values are locally lower with hourly values less
than 1.5-2" and 3" values less than 3". So an isolated incident
or two of flash flooding remains possible more likely over the
next few hours (through 06z) than into late overnight hours.

Gallina

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!-TvB5wH1yA2rEBw5_ycJhpkLeoKNTS-Ovu9k5jlIx-qJ2pkeb0t11tRXvyqCe5r2sRyr= ukq0ka5--mZ0V5dP_wCKRGU$ for graphic product...

ATTN...WFO...SGF...TSA...

ATTN...RFC...KRF...MSR...ORN...TUA...NWC...

LAT...LON 37839174 37359132 36779169 36529332 36329416=20
36139587 36179651 36579663 36769627 36979505=20
37359379 37769264=20

=3D =3D =3D
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AWUS01 KWNH 162003
FFGMPD
ILZ000-MOZ000-170001-

Mesoscale Precipitation Discussion 0114
NWS Weather Prediction Center College Park MD
401 PM EDT Thu Apr 16 2026

Areas affected...a small part of Missouri

Concerning...Heavy rainfall...Flash flooding possible

Valid 162001Z - 170001Z

Summary...Isolated, slow-moving thunderstorms could cause
localized flash flooding for the next few hours (through 00Z/7p
central).

Discussion...A localized cluster of thunderstorms has become
established across central Missouri. The storms have developed in
response to strong insolation/surface destabilization beneath a
very cold mid/upper wave (-18C at 500 hPa). The storms are also
in a very localized area where mid-level flow drops off
substantially, with right-moving storm motions falling to around
5-10 knots per point forecast soundings. This explains recent
behavior of the storm cluster very near Osage Beach, MO, where
MRMS estimates of 1+ inch/hr in that area were already exceeding
local FFG.

Given the weak forcing for ascent, convective coverage is in
question. Persistence of ongoing activity - or perhaps additional
slow-moving cluster(s) of convection could produce 1 inch/hr rain
rates at times. Again, these rates could exceed FFG, and given
sensitive local terrain in the region, another instance or two of
flash flooding cannot be completely ruled out. This risk will
likely be diurnally driven and lessen some after sunset.

Cook

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!-ObucWhVuhSJtJ-DCrbSpVcGeYPrECRaPTiEJb1XmBzxTkejYnTMq5FUaz6gFsNiaqkA= M_oO_IyUC9okdjLdiTlDbSA$ for graphic product...

ATTN...WFO...EAX...LSX...PAH...SGF...

ATTN...RFC...KRF...MSR...ORN...NWC...

LAT...LON 38919228 38839074 38279022 37459022 37119109=20
37199248 37689329 38099339 38809317=20

=3D =3D =3D
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AWUS01 KWNH 171811
FFGMPD
WIZ000-ILZ000-MOZ000-MNZ000-IAZ000-180010-

Mesoscale Precipitation Discussion 0115
NWS Weather Prediction Center College Park MD
210 PM EDT Fri Apr 17 2026

Areas affected...Northeast MO...Western and Northern IL..Eastern
IA...Far Southeast MN...Central and Southern WI

Concerning...Heavy rainfall...Flash flooding likely

Valid 171810Z - 180010Z

SUMMARY...Rapid convective development is expected over highly
saturated soils this afternoon. Anomalous moisture and instability
will support rainfall rates of 1 to 2 inches/hour. While
individual cell motions will be fast, cell-training will lead to
localized totals of 2 to 4 inches, making flash flooding likely
given the sensitive antecedent conditions.

DISCUSSION...GOES-E Day Cloud Phase RGB satellite imagery and
surface observations indicate rapid destabilization across the
Upper Midwest ahead of an ejecting upper-level trough and
approaching strong cold front. A 40 to 50+ kt southwesterly
low-level jet is fostering intense warm air advection and moisture
transport into the region, resulting in an anomalously moist and
unstable airmass for mid-April (PWATs climbing to ~1.25 inches and
MLCAPE of 1500 to 3000 J/kg).

Convective initiation is expected imminently as the cap erodes,
particularly near surface waves analyzed over north-central IA and
southeast MN which are locally enhancing convergence. Deep-layer
ascent will continue to increase this afternoon and evening as a
strong shortwave/jet streak rounds the base of the trough and
approaches from the west. Convective mode is expected to feature a
mix of supercells and organized multicell clusters.

While strong deep-layer shear (40 to 50+ kts) will promote fast
individual cell motions to the northeast, the southwesterly
steering flow is largely parallel to the low-level jet axis and
lifting warm front. This alignment will strongly favor corridors
of cell-training and repeating rounds of heavy rainfall over the
same areas. High-efficiency updrafts will be capable of producing
1 to 2 inch/hour rainfall rates, with the 12Z HREF signaling
localized swaths of 2 to 4 inches through 00Z.

The primary driver for the flash flood threat is the highly
sensitive antecedent conditions. Recent NASA SPoRT 0 to 10 cm soil
moisture data indicates very moist if not saturated soils (80 to
100%) across much of the region, and USGS streamflow networks show
running waterways are already elevated. With minimal infiltration
capacity, the intense 1 to 2 inch/hour rates will to convert to
enhanced runoff concerns, and likely promoting scattered areas of
flash flooding which will include some localized urban impacts as
well.

Orrison

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!9hjs2Z_oHmyo18eoaSQu7i3KoZD9Delq5_o_Aeyu83kiVMQIawM1h87TuD-4LEItpLhN= MhaDX-LNgGe5ulc54SN8dxk$ for graphic product...

ATTN...WFO...ARX...DLH...DMX...DVN...EAX...GRB...ILX...LOT... LSX...MKX...MPX...

ATTN...RFC...KRF...MSR...NWC...

LAT...LON 45659058 45318891 44168851 42578857 41148902=20
40108946 39429028 39319154 39769277 40559338=20
41339334 43079263 44399214 45129163=20

=3D =3D =3D
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AWUS01 KWNH 171904
FFGMPD
MOZ000-OKZ000-KSZ000-NEZ000-180102-

Mesoscale Precipitation Discussion 0116
NWS Weather Prediction Center College Park MD
303 PM EDT Fri Apr 17 2026

Areas affected...portions of southern and eastern Kansas into
northwestern Missouri

Concerning...Heavy rainfall...Flash flooding possible

Valid 171902Z - 180102Z

Summary...Flash flooding is possible as storms expand in coverage
and intensity across the discussion area through 00Z/7p central.

Discussion...Convective initiation has occurred in earnest along a
synoptic front extending from near St. Joseph, MO to near Wichita,
KS over the past half hour. The storms are in an extremely
unstable environment, with 2000-3000 J/kg MLCAPE and 1.2-1.5 inch
PW values supporting heavy rainfall. The front and initial
convection was also oriented parallel to deep southwesterly
steering flow aloft, suggestive of areas of training as storms
mature over the next 1-2 hours. The localized training (and
perhaps cell mergers where individual cells can move right of mean
flow) should result in a few spots of 1.5 inch/hr rain rates that
could result FFG exceedance and flash flooding with time.

Trends through the night will ultimately depend on the degree of
convective coverage and any upscale growth into linear segments
that could materialize. Even if the dominant storm mode becomes
linear, local training axes are likely to materialize and enhance
flash flood risk. These trends, along with any potential
development out ahead of the main frontal band, will be monitored
for any corridors of significant flash flood potential through the
evening hours.

Cook

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!_6urUHJHWAXBLoWXgUTS01fJG-k_8qnlfcUOHJLu-Nf-cVPdz3_l-tPy6jQQo3CpjNI9= 066vCnaiDF9ytCYfuFMT224$ for graphic product...

ATTN...WFO...DDC...EAX...ICT...OAX...OUN...SGF...TOP...

ATTN...RFC...KRF...TUA...NWC...

LAT...LON 40579404 40529265 39909261 37869402 37089542=20
36999727 37289839 38509719 40219524=20

=3D =3D =3D
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AWUS01 KWNH 172337
FFGMPD
MIZ000-INZ000-WIZ000-ILZ000-IAZ000-180434-

Mesoscale Precipitation Discussion 0117
NWS Weather Prediction Center College Park MD
735 PM EDT Fri Apr 17 2026

Areas affected...central/northern Illinois, much of Wisconsin,
upper Peninsula of Michigan, western Indiana

Concerning...Heavy rainfall...Flash flooding likely

Valid 172334Z - 180434Z

Summary...Flash flood potential continues especially across
Wisconsin and northern Illinois. This threat will shift eastward
through the evening hours.

Discussion...A mix of linear and clustered convection continues to
migrate east/northeastward across the discussion area. Areas of repeating/training were noted across far southern Wisconsin - and
that area remains sensitive from prior heavy rainfall over the
past several days. FFGs near/downstream of ongoing convection in
southern Wisconsin are in the 1 inch/hr range (locally lower),
with urban impacts from heavy rain expected in the Milwaukee area
over the next 1-2 hours or so. Flash flooding remains likely
there.

Farther north, scattered convection has matured over central
Wisconsin just ahead of a synoptic cold front despite widespread
convective overturning. Instability profiles remain supportive of
strong/deep convection in the short term (next couple hours),
though the longevity of this convection is in question with
eastward extent. Nevertheless, widespread impacts from recent
heavy rain, swollen watersheds, and snow melt have left the region
very sensitive (FFGs near 0 in the UP of Michigan, also <1 inch/hr
elsewhere in parts of northeastern Wisconsin), and localized flash
flooding remains possible.

Cells in the southern part of this elongated conpmex (exiting
southeastern Iowa) are more linear in nature, though a few cells
have developed over west-central Illinois that should merge with
this line over the next few hours. Ground conditions aren't as
sensitive in central Illinois compared to farther north. Flash
flooding may be more isolated/dependent on local rain rate
enhancement from these mergers.

Eventually, this elongated complex will shift eastward through
northeastern Illinois and into western Indiana, with at least
isolated flash flood potential continuing through 05Z/midnight
central.

Cook

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!75sQHgPWBmHMjZ1Iw9XEB_ZKL_6aH3-pygDpV2_kNNOuyft9zc_2YNqGB8JtW2UbmLfK= YzgLHaEoDJkopQwKKRSvHJA$ for graphic product...

ATTN...WFO...ARX...DLH...DVN...GRB...ILX...IND...IWX...LOT... LSX...MKX...MQT...

ATTN...RFC...MSR...TIR...NWC...

LAT...LON 46768913 46698706 46338613 44718704 42648721=20
41438661 40218642 39408761 39449008 40039107=20
40969098 42259046 43959061 45999024=20

=3D =3D =3D
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AWUS01 KWNH 172339
FFGMPD
MIZ000-INZ000-WIZ000-ILZ000-IAZ000-180434-

Mesoscale Precipitation Discussion 0117
NWS Weather Prediction Center College Park MD
738 PM EDT Fri Apr 17 2026

Areas affected...central/northern Illinois, much of Wisconsin,
upper Peninsula of Michigan, western Indiana

Concerning...Heavy rainfall...Flash flooding likely

Valid 172334Z - 180434Z

Summary...Flash flood potential continues especially across
Wisconsin and northern Illinois. This threat will shift eastward
through the evening hours.

Discussion...A mix of linear and clustered convection continues to
migrate east/northeastward across the discussion area. Areas of repeating/training were noted across far southern Wisconsin - and
that area remains sensitive from prior heavy rainfall over the
past several days. FFGs near/downstream of ongoing convection in
southern Wisconsin are in the 1 inch/hr range (locally lower),
with urban impacts from heavy rain expected in the Milwaukee area
over the next 1-2 hours or so. Flash flooding remains likely
there.

Farther north, scattered convection has matured over central
Wisconsin just ahead of a synoptic cold front despite widespread
convective overturning. Instability profiles remain supportive of
strong/deep convection in the short term (next couple hours),
though the longevity of this convection is in question with
eastward extent. Nevertheless, widespread impacts from recent
heavy rain, swollen watersheds, and snow melt have left the region
very sensitive (FFGs near 0 in the UP of Michigan, also <1 inch/hr
elsewhere in parts of northeastern Wisconsin), and localized flash
flooding remains possible.

Cells in the southern part of this elongate complex (exiting
southeastern Iowa) are more linear in nature, though a few cells
have developed over west-central Illinois that should merge with
this line over the next few hours. Ground conditions aren't as
sensitive in central Illinois compared to farther north. Flash
flooding may be more isolated/dependent on local rain rate
enhancement from these mergers.

Eventually, this elongated complex will shift eastward through
northeastern Illinois and into western Indiana, with at least
isolated flash flood potential continuing through 05Z/midnight
central.

Cook

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!9U-h3PbHAPaEvnkDE8b8ojujiT2ikJcvFmDdocidQB9F7rW9CG0HfjZD7aSshrypXflm= 0uVx1ZhowZi6PlF2XOrL6hQ$ for graphic product...

ATTN...WFO...ARX...DLH...DVN...GRB...ILX...IND...IWX...LOT... LSX...MKX...MQT...

ATTN...RFC...MSR...TIR...NWC...

LAT...LON 46768913 46698706 46338613 44718704 42648721=20
41438661 40218642 39408761 39449008 40039107=20
40969098 42259046 43959061 45999024=20

=3D =3D =3D
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AWUS01 KWNH 180043
FFGMPD
ILZ000-MOZ000-ARZ000-OKZ000-KSZ000-180641-

Mesoscale Precipitation Discussion 0118
NWS Weather Prediction Center College Park MD
842 PM EDT Fri Apr 17 2026

Areas affected...northern/central/eastern Oklahoma, southeastern
Kansas, southern/central Missouri, northwestern Arkansas

Concerning...Heavy rainfall...Flash flooding possible

Valid 180041Z - 180641Z

Summary...Isolated instances of flash flooding remain possible
through 06Z/1a central.

Discussion...Ongoing convection has largely organized into an
extensive linear complex extending from near Osage Beach, MO
west-southwestward through Ponca City and Gage, OK. The storms
are mostly undercut by composite synoptic front/outflow, although
a few elements in central Missouri and far north-central Oklahoma
remain surface-based. The storms are migrating eastward between
35-45 knots while exhibiting localized training and areas of 1-2
inch/hr rain rates at times. These rates should be enough for
isolated flash flooding as FFG thresholds are generally in the
1-1.5 inch/hr range especially from north-central Oklahoma
eastward.

Storms will be maintained through the overnight hours by abundant
instability (1000-2500 J/kg MLCAPE) and strengthening low-level
flow oriented perpendicular to the aforementioned front/outflow,
maintaining robust updrafts and occasional training. Cells may
tend to weaken some in east-central Missouri, but re-development
over western Oklahoma near a front/dryline intersection should
maintain the heavy rain risk through at least 06Z/1a central
tonight. Flash flooding is expected on at least an isolated basis
where training is most pronounced, with terrain influences in
southwestern Missouri also likely playing a role in enhancing
flash flood risk. Lastly, models suggest that the ongoing
convective band will gradually develop southeastward toward the
I-40 corridor in Oklahoma through the night.

Cook

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!8uiQ__KyH0yp5gD3LVLtiqN8N1vgyEat01kFbc0VsJSyK8Qphlh3hQqt4IJgyiwUMQIe= xQ9i_b7j_xr2DclgdMvU51Y$ for graphic product...

ATTN...WFO...EAX...ICT...LSX...LZK...OUN...PAH...SGF...TOP...
TSA...

ATTN...RFC...KRF...MSR...ORN...TUA...NWC...

LAT...LON 39309207 38969054 37709043 36569135 35499386=20
34529681 34489883 35219970 36259956 36939828=20
37899631 38929406=20

=3D =3D =3D
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AWUS01 KWNH 181945
FFGMPD
LAZ000-TXZ000-190145-

Mesoscale Precipitation Discussion 0119
NWS Weather Prediction Center College Park MD
344 PM EDT Sat Apr 18 2026

Areas affected...Southeast TX...Southwest LA

Concerning...Heavy rainfall...Flash flooding possible

Valid 181945Z - 190145Z

SUMMARY...Potent thunderstorms capable of producing >2"/hr
rainfall rates over the urbanized communities of southeast TX and
southwest LA could cause localized urban flash flooding.

DISCUSSION...Visible satellite and Doppler Radar show a bubbling
field of convection over southeast TX and southwest LA in advance
of an approaching strong cold front. Additional surface based
heating this afternoon will yield over 1,500 J/kg of MLCAPE along
the I-10 corridor. Winds in advance, and in wake, of the cold
front are NErly while winds within the 700-200mb layer are firmly
out of the WSW. This is supporting effective bulk vertical wind
shear levels that the RAP suggests could surpass 40 kts. This
would allow for thunderstorms to have more longevity than typical
"pop-up" or "garden variety" storms. HRRR and RAP area averaged
soundings show warm cloud layers up to 12,000ft deep and skinny
CAPE profiles that found in typical warm rain processes. As 850mb
and 700mb weaken over the region this evening, the concern is for
additional thunderstorm development either along the cold front or
induced by the growing cold pool.

Given the favorable thermodynamic environment and increasing PWs
that reach 2.0" east of Houston this evening, the concern is for

2"/hr rainfall rates that manifest over urbanized environments.

The 12Z HREF does show low-chance probabilities (10-30%) from the
Houston suburbs on east into southwest LA this afternoon and
evening. The vast majority of the expected rainfall over southeast
TX and southwest LA this afternoon is welcomed (severe and extreme
drought for many), which is also evident in the 1-hr FFGs that are
no lower than 2" area wide. That said, the potential for
slow-moving and repeating rounds of storms, combined with
anomalous PWs and ample instability aloft, could cause localized
flash flooding in urbanized settings that contain a greater
concentration of hydrophobic surfaces. Low-lying areas with poor
drainage are also susceptible to flash flooding this afternoon.

Mullinax

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!9x_hjSr_ftys34SFugzCvxjT-H0aqr-0ltdAUpbxeqrkiGilLjiBwS_-XpRE3GUtr1g_= A55YawAS8oeq-cWzDYFgzAg$ for graphic product...

ATTN...WFO...HGX...LCH...

ATTN...RFC...FWR...ORN...NWC...

LAT...LON 30589389 30569330 30069327 29629387 29209491=20
28939574 28839638 28939668 29259658 29709602=20
30369451=20

=3D =3D =3D
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AWUS01 KWNH 201828
FFGMPD
FLZ000-210015-

Mesoscale Precipitation Discussion 0120
NWS Weather Prediction Center College Park MD
227 PM EDT Mon Apr 20 2026

Areas affected...southern FL

Concerning...Heavy rainfall...Flash flooding possible

Valid 201825Z - 210015Z

SUMMARY...Slow moving thunderstorms capable of producing 2 to 3+
in/hr are expected to impact southern FL over the next 4-6 hours.
While a large portion of the area affected is covered by swamp,
there could be impacts to urban areas along the southwest and
southeastern coast.

DISCUSSION...18Z surface observations and satellite imagery showed
a cold front dropping south across Monroe and Miami-Dade counties
along with sea breeze boundaries along the southwestern and
southeastern FL coastlines. Visible satellite and radar imagery
showed the early stages of thunderstorm development with at least
one developed cell 10-15 miles southwest of Miami. SPC
mesoanalysis data showed MLCAPE of 1000-1500 J/kg and PWs of 1.5
to 1.7 inches. Low level flow was from the east to northeast and
deeper layer mean winds were relatively weak from the WNW.

Daytime heating and an apparent lack of CIN across southern FL
will lead to additional rapid thunderstorm development within the
next 1-2 hours along low level convergence boundaries forced by
the cold and sea breeze fronts, and later, subsequent convectively
driven outflow boundaries. Slow movement and brief training of
these cores are likely to produce heavy rainfall rates of 2 to 3+
in/hr with the possibility of storm total rainfall in excess of 5
inches. While the 12Z HREF showed 40 km neighborhood probabilities
of exceeding 3 to 5 inches of 20-40 percent, the likelihood of
these higher rates falling over water or swampland is greater than
that of impacting population centers along the coast. However,
should these higher rates overlap with the Naples/Macro Island
region or east-central Miami-Dade County to the upper Keys, urban
flash flooding will be possible. The flash flood threat is
expected to end from north to south and likely be over with after
00Z as the front moves south of the Peninsula.

Otto

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!8AbXtSs2fP1pYZm6Urke5r5CjAgMjCRLCRbGztQ_qt2Cj4zKjJ7W_3kPEsfLCJ4xBv1L= QWbWIlP__ZXdYNaPHGCKEFU$ for graphic product...

ATTN...WFO...KEY...MFL...TBW...

ATTN...RFC...ALR...NWC...

LAT...LON 26368187 26078093 25858011 25258007 24988041=20
25138135 25888205=20

=3D =3D =3D
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AWUS01 KWNH 201932
FFGMPD
TXZ000-210009-

Mesoscale Precipitation Discussion 0121
NWS Weather Prediction Center College Park MD
331 PM EDT Mon Apr 20 2026

Areas affected...Central TX

Concerning...Heavy rainfall...Flash flooding possible

Valid 201929Z - 210009Z

Summary...Additional development of efficient, shallow convection
containing periodic 1.5-2"/hr rainfall rates will maintain the
threat of scattered flash flooding this afternoon over portions of
Central TX.

Discussion...Recent radar mosaic over Central TX depicts an area
of slow moving and efficient showers and thunderstorms which has
persisted through the morning and afternoon hours. Over the last
hour or so, a cell within the broader precipitation shield between
San Antonio and San Marcos has exhibited an uptick in hourly
precipitation rates to 1.5-2"/hr, or 0.50-0.63"/15 minutes per
recent observations, MRMS, and KEWX data. When combined with slow
cell storm motions estimated at 10 kts, this storm led to a quick
uptick in CREST Unit Streamflows to 200-600 cfs/smi where a Flash
Flood Warning was recently issued.

This activity is occurring downstream of an approaching
upper-trough and left exit region jet streak in Northern Mexico to
support broad ascent across the region. At the low levels, an axis
of modest 850-700 mb layer convergence and WAA is also noted just
upwind of this activity. ACARS soundings near the heaviest showers
and thunderstorms suggest a very moist and saturated column from
the surface to 600 mb and 400-500 J/kg of MUCAPE to support
efficient collision-coalescence processes in this activity. While
the instability profile is very shallow, it is somewhat higher
than what CAMS are initializing with (100-250 J/kg) in this area,
which could partially explain why the observed rainfall is more
robust than what is modeled. That said, the RAP does suggest the
aforementioned low-level forcing will persist through the
afternoon hours while the upper-trough approaches for the west.
Thus, the threat of scattered flash flooding will continue through
the afternoon as new cells with periodic 1.5-2"/hr rates could
develop and overlap with the area of current heavy rainfall,
leading to additional totals of 2-3".

Asherman

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!6P27gS0htMUt6ruBzVjQGTOBciYb1I84fU-8LYNmHZqsrW2YvQ28M3ERE9FmwAUoPBGt= AyRfqbg7HBFjdj823bTghhI$ for graphic product...

ATTN...WFO...CRP...EWX...HGX...SJT...

ATTN...RFC...FWR...NWC...

LAT...LON 30409962 30379879 30309766 30009691 29409657=20
28979693 28989818 29339916 29929974=20

=3D =3D =3D
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AWUS01 KWNH 210026
FFGMPD
TXZ000-210504-

Mesoscale Precipitation Discussion 0122
NWS Weather Prediction Center College Park MD
825 PM EDT Mon Apr 20 2026

Areas affected...Central TX

Concerning...Heavy rainfall...Flash flooding possible

Valid 210024Z - 210504Z

Summary...Additional thunderstorms are developing over portions of South-Central TX this evening. These cells will maintain the
threat of flash flooding as they could train and overlap with
areas of heavy rainfall earlier today.

Discussion...Radar across South-Central TX depicts a rapid
expansion in thunderstorm coverage and intensity along the leading
edge of a shortwave near the Big-Bend of TX. At the same time, an
axis of persistent shallow convection northeast of San Antonio was
finally showing signs of weakening after producing 2-4" of
rainfall this afternoon. This activity was quite impactful earlier
today, and 1-2"/hr rainfall rates led to at least one report of a
swift water rescue near Live Oak TX where CREST Unit Streamflows
eclipsed 900 cfs/smi at times.

With that in mind, the concern is for additional thunderstorms
containing 1-1.5"/hr rainfall rates to expand southwest of San
Antonio, in turn leading to periods of training/repeating near
areas impacted earlier today. This scenario is supported by recent
runs of the HRRR (which is an slow but overall has the best handle
on the situation). Taking into account the timing of the HRRR,
this suggests the threat of scattered flash flooding should
persist through 4-5Z tonight. Localized rainfall amounts of 1-2"
could support additional considerable flash flooding impacts,
especially if they fall atop the areas of heaviest rainfall today
(highlighted in red).

Asherman=20

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!-pgGySLa8E2fX8z1a-v1EJ-5dByc4dC3VwIx7_d_Lp_Oyn3qKBs_LqqdACbFnEkn5076= LY9CTpEWQN9KPvCUyWfLKis$ for graphic product...

ATTN...WFO...EWX...

ATTN...RFC...FWR...NWC...

LAT...LON 30109900 30009752 29279747 28959854 29129944=20
29649956=20

=3D =3D =3D
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AWUS01 KWNH 211000
FFGMPD
TXZ000-211530-

Mesoscale Precipitation Discussion 0123
NWS Weather Prediction Center College Park MD
559 AM EDT Tue Apr 21 2026

Areas affected...Triangle of Central Texas...

Concerning...Heavy rainfall...Flash flooding possible

Valid 211000Z - 211530Z

SUMMARY...Flash flooding risk possible given slow
moving/back-building warm-advective shallow but efficient showers/thunderstorms. Rates of 1-1.25"/hr are possible with
localized 2-3" totals.

DISCUSSION...A very effective dynamic environment is helping to
draw above normal moisture into a favorable ascent pattern over
the next few hours across the Triangle of central Texas. GOES-E
WV suite depicts a decaying MCV across southeast TX along the
southeast periphery of favorable mid to upper-level divergent
pattern along the northeast quadrant of a 70kt 3H west to east jet
along/north of 30N. Combined with NW to SE diffluent pattern from
500-250mb providing strong divergence for effective convective
outflow. However, it is also directing strong ageostrophic
forcing by helping to accelerate the early morning western Gulf
jet streak fluxing enhanced low level moisture northward into the
isentropic ascent plane. CIRA LPW along with VWP vectors denote
core of west Gulf jet is propagating 20-25kts in the core of .8 to
1" moisture in the surface to 850mb layer. Combine this with the
axis of 700-500 mid-level moist flow from the subtropical eastern
Pacific results in combined PW values nearing 1.5" near the best
isentropic ascent currently through the San Saba River Valley.

As such, recent 10.3um EIR and RADAR show increasing shallow
convective activity along the NW to SE oriented DPVA into the best diffluence/divergence region downstream. The only limiting factor
is the lack of higher theta-E air resulting in a broader unstable
layer. Currently, it is limited to 100-250 J/kg of MUCAPE but
only expected to increase toward 500 J/kg toward mid-morning as
the core of the western Gulf air reaches the area of concern.=20
Deep layer flux and ascent should allow for solid convergence and
low level precipitation development likely with smaller droplets
in warm-cloud process generation. This should allow for increased
rainfall rates, but without the greater vertical depth, is likely
to be limited to the 1.25" range at max. Convective cells are
likely to move toward the northeast, but with continued south to
southwest low level inflow, propagation vectors should be
supportive of upstream redevelopment/back-building of the shallow
cores. This should allow for increased overall duration to
potentially support highly focused/localized maximum totals of
2-3" through to afternoon.=20

Hydrologically, these maximum totals are at the minimum thresholds
of 1 but more likely 3 hour FFG values in the area, particularly
along the southwest edge of the area of concern. NASA SPoRT LIS
0-40cm soil conditions suggest average saturation around 45-55%
and as such, most rainfall will be beneficial, but an isolated
incident or two of flash flooding is considered possible given the
strong dynamics and setup's history.=20

Gallina

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!_I219mon2hUaIT9iZgkore_06USnlzSqH8nUYqkck59CIiG6-YfaYH-y3ycu4YEpwlLD= 4FbM0lDcXhAwB3fCiFCScWs$ for graphic product...

ATTN...WFO...EWX...FWD...SJT...

ATTN...RFC...FWR...NWC...

LAT...LON 32539720 32209657 31769628 31419629 31169645=20
30919666 30589712 30449755 30679836 31159887=20
31779894 32509834=20

=3D =3D =3D
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AWUS01 KWNH 211535
FFGMPD
TXZ000-212100-

Mesoscale Precipitation Discussion 0124
NWS Weather Prediction Center College Park MD
1133 AM EDT Tue Apr 21 2026

Areas affected...East central Texas

Concerning...Heavy rainfall...Flash flooding possible

Valid 211533Z - 212100Z

Summary...Slow moving heavy showers and thunderstorms continue to
develop across eastern portions of central Texas late this
morning, and are expected to persist going into the early to
middle afternoon hours. Rainfall rates in excess of an inch per
hour may lead to additional instances of flooding through 4 pm
local time.

Discussion...Regional Doppler radars and GOES-E satellite imagery
continue to indicate a swath of heavy rainfall with embedded
convection, centered mainly between San Saba and Columbus, Texas
late this morning. This is primarily developing as a result of
enhanced ascent from a 700 mb trough axis and mid-level shortwave
intersecting moist 20-30 knot 850 mb southerly flow, and this band
has been maintaining itself over the past few hours with only
limited latitudinal displacement over the morning hours.

The latest CAM guidance suggests the potential for scattered QPF
maxima on the order of 1-3 inches through 21Z, with recent ARW
runs most impressive with up to 4 inches possible during that
time. The soils are becoming increasingly saturated and prone to
additional flooding, with some regions getting 2 to 4 inches in
just the past 12 hours as depicted in the graphic, and flash flood
guidance is dropping in response to this. Even though the
instability parameters are modest and most rainfall rates should
be 1.5 inches per hour or less, some instances of flash flooding
will be possible given the duration of the event.

Hamrick

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!6rZMdZryMnN1h6U47HcOTCMKMYBmebTgM_8KHuzizEgtqpQj8aSaafmjYcXXKRj4CWEH= y070S3biTHnSDXrWh992LpM$ for graphic product...

ATTN...WFO...EWX...FWD...HGX...SJT...

ATTN...RFC...FWR...NWC...

LAT...LON 31399745 31079654 30659580 30219534 29699511=20
29059518 28879550 28899585 28989632 29229708=20
29909767 30189812 30509848 30959864 31259830=20 =20=20=20=20=20=20=20=20=20=20=20=20

=3D =3D =3D
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AWUS01 KWNH 222045
FFGMPD
TXZ000-230130-

Mesoscale Precipitation Discussion 0125
NWS Weather Prediction Center College Park MD
444 PM EDT Wed Apr 22 2026

Areas affected...central TX to middle/upper TX Coastal Plain

Concerning...Heavy rainfall...Flash flooding possible

Valid 222042Z - 230130Z

Summary...Isolated flash flooding will be possible across portions
of central TX into the middle and upper TX Coastal Plain through
the early evening. Localized rainfall rates of 2-3 in/hr (locally
higher) will be possible which could lead to runoff problems where
overlap occurs with urban areas or other locations with poor
drainage, especially given above average rainfall over the past
few days.

Discussion...Area radar imagery across southeastern TX at 2015Z
showed scattered thunderstorms across the middle and upper TX
Coastal Plain, mainly east of U.S. Hwy 77. SPC mesoanalysis data
from 20Z showed uninhibited MLCAPE of 1000-2000 J/kg and PWs of
1.3 to 1.6 inches across the region. The storms were located
within northwest flow aloft between two vorticity maxima, one over
the Gulf, south of western LA within a region of effective bulk
shear between 30-35 kt, and a second vort max over northeastern
TX. Bulk shear values dropped off significantly to the north and
low level onshore flow between 925-850 mb of less than 15 kt
appeared to be limiting organization over land. However, cell
motions were fairly slow at 5-15 kt and portions of the region
have picked up 2-4 inches of rain over the past 4 days, higher to
the west near I-35.

Therefore, while cells were not very organized, slow movement and
outflow interactions/mergers could result in hourly rainfall of
2-3 inches (perhaps locally higher) and localized totals of 2-4
inches through 01Z. While congealing outflows could result in some
westward migration of activity toward 00Z, the overall footprint
of ongoing storms is not expected to change much over the next few
hours. Isolated higher rainfall maxima could result in flash
flooding should they overlap with more sensitive ground
conditions, whether that be an urban location or locally
hydrologically sensitive area due to recent rainfall.

Otto

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!_3LvrLfgRtViQVo-_a9F6P1Xv6F7kfWFSRPquiOqE_-jVWwsbw2FBSSnmKKdI1qasTBI= rsQcycUFdREyrZbFU_yPA64$ for graphic product...

ATTN...WFO...CRP...EWX...HGX...LCH...

ATTN...RFC...FWR...NWC...

LAT...LON 30799449 30649406 30429393 29889416 29389487=20
28859565 28849669 29109711 29429747 29689764=20
29999763 30269730 30379683 30509592 30759510=20 =20=20=20=20=20=20=20=20=20=20=20=20

=3D =3D =3D
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AWUS01 KWNH 232000
FFGMPD
MOZ000-IAZ000-KSZ000-NEZ000-240100-

Mesoscale Precipitation Discussion 0126
NWS Weather Prediction Center College Park MD
359 PM EDT Thu Apr 23 2026

Areas affected...northeastern KS, southeastern NE, southwestern
IA, northwestern MO

Concerning...Heavy rainfall...Flash flooding possible

Valid 231956Z - 240100Z

Summary...Isolated instances of flash flooding will be possible
from northeastern KS into southeastern NE, western IA and
northwestern MO. Training of thunderstorms will produce hourly
rainfall of 1-2 in/hr with peak rainfall totals of 2-4 inches
possible, through 01Z.

Discussion...1945Z radar imagery showed a broken line of
thunderstorms extending from south-central MN down to the NE/KS
border, just ahead of a cold front. A cyclonic swirl was observed
on visible imagery over northern KS, related to a low to mid-level
vorticity max located just north of the surface triple point.
Strong to severe thunderstorms were ongoing in the vicinity of
Omaha, NE with rapid development noted south of Omaha to the NE/KS
border. SPC mesoanalysis data from 19Z showed 2000-3000 J/kg
MLCAPE from western IA into east-central KS ahead of the cold
front with little to no CIN present.

While thunderstorm activity to the north over western IA continues
to grow and expand downstream toward central IA through 00Z, newer
development to the south is also expected to expand within the
unstable environment ahead of the front and favorably
diffluent/divergent jet pattern aloft. A general eastward
advancement of the line is expected but an inflection or two
within the line of storms is anticipated, allowing for the
increased potential for brief training from the NE/IA border down
into northeastern KS as line orientation matches that of the mean
steering from from the southwest. Elements of training will be
capable of 1-2 in/hr rates and there will be isolated potential
for 2-4 inches through 01Z as the line of thunderstorms advances
off toward the east.

Otto

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!77pisuZzS7nVKIjm86sEMRBSU92gf0hG8Jrg_GINe5iPA9dGpBPfqkUmC-wLry78e5nO= Fsv2NO7BvOXPtH-oP3LAvqs$ for graphic product...

ATTN...WFO...DMX...EAX...ICT...OAX...TOP...

ATTN...RFC...KRF...MSR...TUA...NWC...

LAT...LON 41949521 41839435 41249367 39789434 37989595=20
38109739 38699787 39899740 41119655=20

=3D =3D =3D
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AWUS01 KWNH 240029
FFGMPD
MIZ000-WIZ000-ILZ000-MNZ000-IAZ000-240600-

Mesoscale Precipitation Discussion 0127
NWS Weather Prediction Center College Park MD
828 PM EDT Thu Apr 23 2026

Areas affected...Upper MS Valley into MN Arrowhead/western U.P. of
MI

Concerning...Heavy rainfall...Flash flooding possible

Valid 240027Z - 240600Z

Summary...Widely scattered instances of flash flooding will be
possible across northeastern IA/southeastern and northeastern MN
into WI and the western U.P. of MI over the next 6 hours. Training
of heavy rain is expected to produce 1-2 in/hr rates with isolated
totals in the 1 to 3 inch range.

Discussion...Area radar imagery at 00Z showed an intense squall
line which extended from north-central IA into northeastern KS,
tracking slowly toward the east-northeast. Meanwhile, less
organized convection was noted to the north near western Lake
Superior into central WI along with additional scattered storms in
eastern IA. Estimated MLCAPE from 00Z SPC mesoanalysis data showed
500 to 1500+ J/kg from northeastern IA into the western half of WI
(highest to the south, ahead of the SQLN). MUCAPE up to 1000 J/kg
was estimated across the eastern MN Arrowhead, north of a surface
warm front. Aloft, a 90-100 kt jet streak was captured via GOES
East DMV over western MN, with diffluent and divergent winds
within its right-entrance region, likely supporting the recent
uptick in convective activity over eastern IA.

Expectations are for the squall line to continue advancing toward
the ENE, while coverage and intensity increases regarding the
activity from eastern IA into WI, owing to strengthening jet
support in the upper levels. However, one limiting factor for
maintaining convective intensity through the first half of the
night is the forecast for weakening instability with time and with
northern extent. On the other hand, portions of the region have
seen over 300 percent of normal rainfall over the past 2 weeks
which will contribute to quicker runoff from heavy rain. Lingering
snow cover in limited northern locations may also contribute to
excess runoff from added heavy rainfall. Rainfall rates of 1 to 2
in/hr within areas of training from northeastern IA into
southeastern MN and portions of western/central WI can be expected
at times, with storm total rainfall of 1 to 3 inches in a couple
of locations. These widely scattered instances of heavier rainfall
could lead to flash flooding within portions of the Upper MS
Valley through ~06Z.

Otto

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!6kgfqTSwxWwKfzCXp6PG-UAyu1foOIh4ilYhnayi2dXgpRbpViVpumX8fci7fSoUunxJ= twj7iBcBPU6tjsc2DwGSc9s$ for graphic product...

ATTN...WFO...ARX...DLH...DMX...DVN...GRB...MKX...MPX...MQT...

ATTN...RFC...MSR...NWC...

LAT...LON 48228962 47748933 45408862 43648935 42109078=20
41619219 42109326 43829283 45429220 47259153=20
48209035=20

=3D =3D =3D
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AWUS01 KWNH 240111
FFGMPD
OKZ000-KSZ000-240630-

Mesoscale Precipitation Discussion 0128
NWS Weather Prediction Center College Park MD
910 PM EDT Thu Apr 23 2026

Areas affected...southeastern KS, northeastern OK

Concerning...Heavy rainfall...Flash flooding likely

Valid 240109Z - 240630Z

Summary...A focused region of flash flooding is expected to set up
over portions of southeastern KS into northeastern OK through 06Z.
Slow movement/training of cells will lead to hourly rainfall of 1
to 3 inches and storm total rainfall of 2 to 4+ inches over the
next few hours.

Discussion...Area radar imagery across the central Plains at 01Z
showed two intense areas of slow moving convection. First over
eastern KS, over and just northeast of Wichita and a second area
over northern OK, bisecting I-35. The northern cluster of storms
was near the triple point (near ICT) and was associated with an
outflow boundary which intersected to the west, at the triple
point. Both areas have been associated with training and resided
within a very unstable environment with MLCAPE estimated in the
2500-3500 J/kg range (00Z SPC mesoanalysis and 00Z OKC sounding).
Fading visible imagery showed cloud streets oriented with the low
level inflow, south to north, into the northern OK thunderstorms.
The eastern KS/OK border lay beneath a diffluent upper level jet
pattern, favorable for increased ascent over the region.

As the low level jet continues to increase with the diurnal cycle,
exceeding 50 kt over northeastern OK by 03-04Z (recent RAP
forecasts), overrunning of the storm-generated cold pools should
continue to support convective regeneration along the southwestern
flank of the system with WSW to ENE training, while overall
southward propagation occurs gradually with time. The low level
flow is expected to veer by ~06Z which should allow the convective
cluster to advance eastward away from its current initiation point
along the dryline. However, up until that happens, locally heavy
rainfall is expected to support areas of flash flooding with total
rainfall totals of 2 to 4+ inches likely.

Otto

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!_4IhhlNU2-TD0lf6iOAtxNfWHMxiBhR6ZzQMqDoUwtb1AoqbV-UaP8nALEjLyD8ddVPY= CTr8DwZ8JwE5hBk8Xurdt5A$ for graphic product...

ATTN...WFO...ICT...OUN...SGF...TOP...TSA...

ATTN...RFC...TUA...NWC...

LAT...LON 38339621 38269564 37749511 37399499 36559504=20
35959602 35739762 35999840 36709810 37739759=20
38179690=20

=3D =3D =3D
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AWUS01 KWNH 240540
FFGMPD
MOZ000-ARZ000-OKZ000-KSZ000-241135-

Mesoscale Precipitation Discussion 0129
NWS Weather Prediction Center College Park MD
138 AM EDT Fri Apr 24 2026

Areas affected...Central to Northeast OK...Far Southeast
KS...Southwest MO...Northwest AR

Concerning...Heavy rainfall...Flash flooding likely

Valid 240538Z - 241135Z

SUMMARY...Backbuilding and training thunderstorms producing 1.5 to
2.5 inch/hour rainfall rates will pose a significant urban flash
flood threat across northern to northeast Oklahoma early this
morning. Convection will eventually grow upscale into an MCS and
track east-southeastward into the Ozark Plateau through dawn.
Broad totals of 2 to 4 inches are expected, with localized amounts
possibly exceeding 5 inches.

DISCUSSION...Latest radar and satellite trends depict a highly
active convective environment across northern Oklahoma.
Thunderstorms are continuously backbuilding and training along a
well-defined mesoscale outflow boundary, positioned east of a
dryline and ahead of a surface wave transiting a cold front. The
thermodynamic and kinematic environment is exceptionally
supportive of extreme rainfall rates. A strong 40 to 50+ kt
southwesterly low-level jet (LLJ) is impinging directly onto the
outflow boundary, providing intense moisture convergence and
tapping into a robust instability pool characterized by 2000-3000
J/kg of MUCAPE. Furthermore, upper-level divergence associated
with an ejecting trough is providing deep-layer ascent to sustain
robust convective updrafts.

Currently, this setup is fostering high-efficiency rainfall rates
of 1.5 to 2.5 inches/hour. Given the quasi-stationary nature of
the boundary and the parallel alignment of the convection to the
deep-layer steering flow, persistent cell-training is occurring.
This will pose a significant, localized flash flood threat over
the highly sensitive urban footprints from Stillwater through the
Tulsa metro over the next few hours.

As the cold pool eventually strengthens and coalesces, convection
is expected to grow upscale into an east-southeast propagating
MCS. However, the strong southwesterly LLJ will continue to favor
persistent backbuilding on the southwest flank of the convective
mass, effectively slowing the forward translation of the heaviest
rainfall cores. High-resolution guidance (including the HRRR and
00Z HREF) supports widespread 2 to 4 inch totals, but given the
prolonged training potential, localized storm totals up to 5+
inches are highly probable.

Towards sunrise and through the 12Z time frame, this complex will
push into the Ozark Plateau across southwest Missouri and
northwest Arkansas. As the low-level flow interacts with the
complex topography of the Ozarks, mechanical lift will sustain
high rainfall rates. The steep, flashy basins of this region will
be highly susceptible to rapid runoff from these accumulations,
carrying a localized flash flood threat right through the morning
commute.

Orrison

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!87rVcEPmsU9ex1Yk0K8aWF2Pb8232nBhVf7ItOCXLPVZNzMyriOrFzStjEF4-wbQlPKD= d_jNmt4E0BBYixOlqowwVpI$ for graphic product...

ATTN...WFO...ICT...LZK...OUN...SGF...TSA...

ATTN...RFC...KRF...ORN...TUA...NWC...

LAT...LON 37729347 37429237 36579207 35939265 35409427=20
35209635 35369772 35869835 36199831 36419785=20
36719636 37279469=20

=3D =3D =3D
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AWUS01 KWNH 250442
FFGMPD
MSZ000-LAZ000-ARZ000-TXZ000-251000-

Mesoscale Precipitation Discussion 0130
NWS Weather Prediction Center College Park MD
1240 AM EDT Sat Apr 25 2026

Areas affected...Northeast TX...Far Southeast AR...Northern
LA...Central MS

Concerning...Heavy rainfall...Flash flooding possible

Valid 250440Z - 251000Z

SUMMARY...Locally heavy showers and thunderstorms with some
cell-training concerns can be expected over the next few hours.
Rainfall rates of up to 2 inches/hour may result in some isolated
and mainly urban concerns for flash flooding.

DISCUSSION...The latest radar and satellite imagery shows
convection becoming a little more concentrated across portions of
northeast TX as modest upstream shortwave/jet energy interacts
with a well-defined outflow boundary and the pooling of rather
strong instability along it. Meanwhile, farther east across far
southeast AR and into central MS, an elevated axis of convection
is seeing with cooling convective tops associated with warm air advection/isentropic ascent over the top of a well-established
cold pool.

MUCAPE values across northeast TX and through northern LA and
southwest MS are on the order of 2000 to 3000 J/kg with modest
low-level flow in the 850/925 mb layer of only 10 to 20 kts.
However, there is some deeper layer ascent being facilitated by
upstream shortwave energy that is embedded within the deeper layer
westerly flow. This coupled with the low-level warm air advection
and proximity of the outflow boundary should tend to favor some
convective sustenance and perhaps further expansion of activity
over the next few hours across northeast TX through northern LA
and central MS.

Given the level of instability and with PWs of near 1.5 inches,
some of the rainfall rates may reach 2 inches/hour. Alignment with
the deeper layer westerly steering flow in the 850/300 mb layer
will suggest at least some concerns for localized cell-training,
and this may yield some additional rainfall totals of 3 to 4+
inches. This is also being advertised by some of the 00Z HREF
guidance.

Expect at least an isolated and mainly urban concern for flash
flooding over the next few hours as a result.

Orrison

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!5ZkRTFNNWkfRCJJ2FBXzVe9MqwfN1u3t6urR953tBOnAQk-O2S2ZLVqfSPcLSDOHzWpy= KyTxBcxFRu0DUi3CEEDBNt0$ for graphic product...

ATTN...WFO...FWD...JAN...LCH...LIX...LZK...MOB...SHV...

ATTN...RFC...ALR...FWR...ORN...NWC...

LAT...LON 33529134 33508963 32928865 32198847 31528903=20
31269031 31369280 31829516 32229628 32869624=20
32949521 33049332=20

=3D =3D =3D
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AWUS01 KWNH 252306
FFGMPD
TXZ000-OKZ000-260503-

Mesoscale Precipitation Discussion 0131
NWS Weather Prediction Center College Park MD
704 PM EDT Sat Apr 25 2026

Areas affected...Northeast TX into Southeast OK

Concerning...Heavy rainfall...Flash flooding possible

Valid 252303Z - 260503Z

SUMMARY...A localized flash flood risk exists through the evening
hours across portions of northeast TX into southwest OK.
Supercells will be capable of producing heavy rainfall resulting
in an urban flash flood risk. Additionally, localized cell mergers
near the warm front may also result in isolated flash flooding.

DISCUSSION...Supercell activity is expected through the evening,
with development near a dryline and a warm front near the Red
River. The environment is characterized by extreme instability
(MLCAPE around 4000 j/kg) and strong shear (effective bulk shear
around 50kts). This overlap of ingredients supports supercells
with very large hail and heightened tornado potential (see SPC
tornado watch 144). While these are likely the primary hazards
associated with this convection, an isolated flash flood risk
could also evolve.

Limiting factors for heavy rainfall will be the very steep lapse
rates and some dry air in the mid levels keeping PWs around
1.4-1.6". However, strong mesocyclones within these supercells
will enhance lift and help increase rainfall efficiency. This will
result in heavy rainfall rates, though forecast supercell motions
off to the east-southeast at 10-20 kts should limit duration.
Consequently, the flash flood risk will primarily depend on
supercell mergers or clusters extending duration. This is
certainly a possibility, especially near the warm front where
persistent convergence and storm tracks along the front could
yield some training and local rainfall over 3". Even without cell
training a localized urban flash flood risk exists as these cells
can drop 2" of rain quickly.

Recent HRRR runs seemingly have a decent handle on the expected
convective evolution through the evening hours. The HRRR depicts
an uptick in 850mb moisture transport later this evening into
tonight, which will help sustain activity as convection
increasingly forward propagates. However, with moisture transport
persisting over northeast TX towards the Red River, we will need
to monitor for additional development overnight depending on how
this evenings supercells impact the instability field. If
additional development occurs, the pattern would support some
northwest to southeast training.

Chenard

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!7Hyn8ePr9iIUeGEETHZyqRefzkhOuBk5OioV-2JVecsiaT7eE6mGIDCYy8_-xq3Td85K= BOvq6mqBoX6cyy3scyIbpeM$ for graphic product...

ATTN...WFO...FWD...OUN...SHV...TSA...

ATTN...RFC...FWR...ORN...TUA...NWC...

LAT...LON 34809731 34729657 33959509 33499446 32589480=20
32489608 32769762 33269827 33829861 34169838=20
34509800=20

=3D =3D =3D
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