• DAY2SVR: Nws Storm Prediction Center Norman Ok

    From COD Weather Processor@1:2320/107 to [email protected] on Tue Apr 14 05:57:24 2026
    ACUS02 KWNS 140557
    SWODY2
    SPC AC 140555

    Day 2 Convective Outlook
    NWS Storm Prediction Center Norman OK
    1255 AM CDT Tue Apr 14 2026

    Valid 151200Z - 161200Z

    ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF
    THE SOUTHERN PLAINS TO THE MIDDLE MISSISSIPPI VALLEY AND ACROSS
    EASTERN OHIO INTO PENNSYLVANIA...

    ...SUMMARY...
    Severe thunderstorms posing a risk for large hail, strong wind
    gusts, and a couple of tornadoes will be possible across portions of
    the southern Plains toward the Great Lakes on Wednesday afternoon
    and evening.

    ...Synopsis...

    A shortwave upper trough will eject from the central Plains to the
    Great Lakes on Wednesday. A swath of enhanced southwesterly
    deep-layer flow will extend from the southern/central Plains to the
    Great Lakes/Midwest ahead of this feature. The southern extent of
    the upper trough will move more slowly east, from the southern
    Rockies to the southern High Plains. At the surface, low pressure is
    forecast to be in the vicinity of the Mid-MO Valley/southeast NE
    Wednesday morning, and will shift east/northeast along a warm front
    across IA/southern WI/northern IL through evening. A trailing cold
    front will move across the Upper Midwest and Great Lakes vicinity
    during the nighttime hours as the surface low continue to progress
    northeast into Ontario. Further south, a dryline will extend
    south/southwest across eastern KS into western OK and west-central
    TX. A seasonally moist and unstable airmass will be in place ahead
    of these surface features, focusing severe thunderstorm potential
    during the afternoon and evening. A warm moist and unstable airmass
    will extend eastward across portions of the upper Ohio
    Valley/Northeast.

    ...MO Valley to Lake Michigan vicinity...

    Convection is likely to be ongoing across parts of the region
    Wednesday morning. As a result, uncertainty exists regarding airmass
    recovery and evolution of severe potential Wednesday
    afternoon/evening. Persistent southwesterly flow and warm advection
    ahead of the surface low will maintain a moist airmass. Convection
    should redevelop by late afternoon/evening near the surface low and
    along a surface boundary extending from eastern IA to near the IL/WI
    border. Where heating can occur in the wake of early day convection,
    MLCAPE around 1000-2000 J/kg should develop. Supercell wind profiles
    are evident in forecast soundings, especially near the surface low
    where SRH will be enhanced. Initial cells may pose a risk for hail.
    Tornado potential is a bit more uncertain given aforementioned
    concerns about boundary-layer impacts from early day convection.
    However, at least low potential should exist near the surface low
    and warm front/outflow. A corridor of higher tornado probabilities
    may be needed in subsequent outlooks if confidence in mesoscale
    details and boundary layer recovery increases. During the evening,
    upscale growth into an eastward-advancing line is expected as a
    surface cold front begins to move east across the region, and
    damaging winds will be possible.

    ...Southern Plains...

    Isolated supercells are forecast to develop along the dryline in OK
    into eastern KS/ and eventually portions of MO. Mid to upper 60s F
    dewpoints beneath steep midlevel lapse rates (7.5-8 C/km) will
    support 2000-3000 J/kg MLCAPE by afternoon. Some weak capping is
    noted around 850 mb, which may limit storm coverage in the absence
    of stronger large-scale ascent. Nevertheless, elongated/straight
    hodographs above 2-3 km within a favorable thermodynamic environment
    suggests large to very large hail will be possible with storms that
    develop. A couple of tornadoes also will be possible given modestly
    enlarged and favorably curved low-level hodographs and around 150
    m2/s2 SRH within a narrow corridor near the dryline.

    ...Upper Ohio Valley toward the Northeast...

    Fast deep-layer west/southwesterly flow will overspread a moistening
    low-level boundary layer. Strong heating will support steepening
    low-level lapse rates and cool temperatures aloft will support
    midlevel lapse rates near 7 C/km. This will foster moderate
    destabilization during the afternoon, promoting isolated to widely
    scattered thunderstorm development. Damaging wind gusts and isolated
    hail will be possible with this activity into the evening.

    ..Leitman.. 04/14/2026

    $$

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  • From COD Weather Processor@1:2320/107 to [email protected] on Tue Apr 14 17:40:32 2026
    ACUS02 KWNS 141740
    SWODY2
    SPC AC 141738

    Day 2 Convective Outlook
    NWS Storm Prediction Center Norman OK
    1238 PM CDT Tue Apr 14 2026

    Valid 151200Z - 161200Z

    ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM PARTS OF
    NORTHERN TEXAS AND OKLAHOMA NORTHEASTWARD INTO SOUTHERN
    WISCONSIN...AND FROM NORTHERN OHIO INTO PENNSYLVANIA...

    ...SUMMARY...
    Severe thunderstorms posing a risk for large hail, strong wind
    gusts, and a couple of tornadoes will be possible across portions of
    the southern Plains toward the Great Lakes Wednesday afternoon and
    evening.

    ...Synopsis...
    A positive-tilt upper trough will be located over the central Plains
    on Wednesday and will move across the MS Valley and toward the Great
    Lakes late. Moderate to strong mid to high level southwesterlies
    will exist over much of the central and southern Plains, along with
    cool temperatures aloft. Meanwhile, an upper ridge will hold over
    the Southeast, with moderate winds aloft along the periphery of the
    upper ridge extending from the OH Valley into the Northeast.

    At the surface, low pressure will develop into IA as the upper wave
    moves out of NE and KS. A front/dryline will extend south across
    eastern KS, western OK and west central TX during the day.
    Meanwhile, an elongated stationary front will extend from IA into
    southern WI/MI and into the lower Great Lakes, with more of a warm
    front into NY and southern New England. Mid to upper 60s F dewpoints
    will remain roughly from TX into IA, with lower 60s F dewpoints
    along the length of the stationary front.

    ...TX/OK/KS/IA/MO/IL...
    A focused area of severe storm potential will develop south of the
    developing low and along the dryline during the afternoon. Although
    the wave will be moving away from OK/TX, the dryline should stall
    with strong instability developing and MLCAPE over 3000 J/kg.
    Minimal lift will be required near the dryline to initiate afternoon
    storms, possibly before 21Z. Cells should develop from northwest TX
    across OK and into southeast KS, and gain strength as 50-60 kt
    effective shear acts upon them. Both supercells and bowing
    structures will be possible, with areas of very large hail and
    damaging winds expected. A few tornadoes may occur given the strong
    instability and midlevel lapse rates, despite marginal low-level
    wind fields.

    Farther north, another zone of supercell potential is evident from
    northern MO into IA and western IL late in the day ahead of the
    shortwave trough. Here, deep-layer shear vector orientation will be
    quite favorable for discrete cells, with hail likely. Any early day
    storms may affect warm sector quality, but conditionally, a tornado
    will be possible.

    ...From WI/IL eastward into PA...
    Areas of heating and warm advection toward the frontal zone will
    result in widely scattered afternoon thunderstorms erupting over IL,
    IN, southern WI, northern OH and into western PA by 21Z. Favorable
    deep-layer shear averaging near 40 kt and at least 1500 J/kg MUCAPE
    along this zone will favor storms producing hail and locally
    damaging gusts. Storm modes may be mixed.

    ..Jewell.. 04/14/2026

    $$

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  • From COD Weather Processor@1:2320/107 to [email protected] on Wed Apr 15 05:18:35 2026
    ACUS02 KWNS 150518
    SWODY2
    SPC AC 150516

    Day 2 Convective Outlook
    NWS Storm Prediction Center Norman OK
    1216 AM CDT Wed Apr 15 2026

    Valid 161200Z - 171200Z

    ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF
    NEW YORK AND SOUTHERN VERMONT...

    ...SUMMARY...
    Isolated strong to severe thunderstorms are possible on Thursday
    extending from southeast Missouri across the Ohio Valley and into
    parts of New York.

    ...Synopsis...

    An upper shortwave trough will spread east across the Midwest on
    Thursday, becoming oriented from the Lower Great Lakes to the
    central/southern Appalachians by Friday morning. At the surface, a
    front will sag south/southeast across the Great Lakes. Modest
    southwesterly low-level flow will maintain upper 50s to low 60s F
    dewpoints from the Mid-South into New York/southern New England.
    This should be sufficient for weak to moderate destabilization given
    modestly steep midlevel lapse rates.

    ... New York vicinity...

    Modest height falls are forecast across the region during the
    afternoon and evening within a low-level warm advection regime.
    Moderate to strong deep-layer mid/upper flow will overspread the
    moistening boundary layer, supporting effective shear magnitudes of
    30+ kt. Heating into the mid/upper 70s will lead to steepening
    low-level lapse rates, while cool temperatures aloft (near -12 C at
    500 mb) will support 1000-1500 J/kg MLCAPE. Isolated to scattered
    thunderstorms will develop during the afternoon. An accompanying
    risk of isolated large hail and damaging wind gusts is expected.

    ...Mid-South and Ohio Valley...

    Convection posing a risk for marginal hail may be going across parts
    of the MO Bootheel vicinity Thursday morning. Persistent warm
    advection should allow for airmass recovery by afternoon across this
    area and thunderstorms are forecast to redevelop during the
    afternoon with a continued risk for isolated hail and strong wind
    gusts. Additional isolated convection also develop into the Ohio
    Valley during the afternoon, though the thermodynamic environment
    may be more marginal due to possible morning showers and cloud cover
    lingering, limiting destabilization. However, if storms are able to
    develop, locally strong gusts and marginal hail will be possible.

    ..Leitman.. 04/15/2026

    $$

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  • From COD Weather Processor@1:2320/107 to [email protected] on Wed Apr 15 17:00:59 2026
    ACUS02 KWNS 151700
    SWODY2
    SPC AC 151658

    Day 2 Convective Outlook
    NWS Storm Prediction Center Norman OK
    1158 AM CDT Wed Apr 15 2026

    Valid 161200Z - 171200Z

    ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER MUCH OF
    UPSTATE NEW YORK AND INTO SOUTHERN VERMONT...

    ...SUMMARY...
    A corridor of strong to severe storms is possible Thursday over much
    of central New York into southern Vermont. Isolated strong storms
    may extend southwestward into parts of Arkansas and Tennessee.

    ...Synopsis...
    A fast-moving shortwave trough will move from the OH Valley/Great
    Lakes into NY and PA on Thursday, providing increasing large-scale
    ascent and wind fields. Southwest of this area, a secondary wave is
    forecast to move across MO/AR and to the lower OH Valley by 00Z,
    with cooling aloft.

    At the surface, low pressure will develop east out of lower MI and
    into upstate NY during the afternoon, with strengthening
    west/southwest winds maintaining 50s to near 60 F dewpoints across
    NY and southwest New England. Farther south, a most air mass will
    remain over the lower MS Valley, with 60s F dewpoints from AR into
    southeast MO and western TN.

    ...Northeast...
    Storms are likely to form ahead of the upper wave during the early
    afternoon across western NY and northwest PA, and perhaps beneath
    the upper low over lower MI. The MI activity may contain hail, while
    the NY storms develop into a multifaceted threat.

    Lengthening hodographs across NY and into southwest New England will
    favor cellular storm mode, with a few supercells expected. Hail
    appears probable. A few damaging gusts may develop late in the day
    if activity can produce outflow and become more linear. A tornado
    will be possible as well, especially as cells interact with the warm
    advection zone/warm front where low-level shear will be bit
    stronger, from the Hudson Valley across VT and perhaps into
    southwest NH.

    ...AR/MO/KY/TN...
    Models insist that early day storms will occur from eastern AR into
    western TN, but with little severe potential. In the wake of this
    activity, lapse rates will steepen as cooling aloft overspreads the
    area and surface heating occurs. Ascent will be minimal but warm
    advection from the southwest and a possible residual outflow
    boundary may instigate additional storms from northern AR into TN
    and perhaps far northern MS/AL. A few reports of hail or wind would
    be possible.

    ..Jewell.. 04/15/2026

    $$

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  • From COD Weather Processor@1:2320/107 to [email protected] on Thu Apr 16 05:59:35 2026
    ACUS02 KWNS 160559
    SWODY2
    SPC AC 160557

    Day 2 Convective Outlook
    NWS Storm Prediction Center Norman OK
    1257 AM CDT Thu Apr 16 2026

    Valid 171200Z - 181200Z

    ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS
    OF OKLAHOMA...KANSAS...MISSOURI...IOWA...ILLINOIS...FAR SOUTHEAST MINNESOTA...AND WISCONSIN...

    ...SUMMARY...
    Widespread severe thunderstorms are expected from parts of the
    southern Plains to the Middle and Upper Mississippi Valley vicinity
    Friday into Friday night. Tornadoes, possibly strong, very large
    hail, and swaths of damaging winds will be possible.

    ...Southern Plains to Upper Midwest...

    A potent upper trough from is expected to eject over the Plains and
    Upper Midwest on Friday. Strong deep-layer southwesterly flow will
    overspread the region early in the forecast period, with 850-700 mb
    flow around 40-50 kt common from parts of OK/KS into WI. At the
    surface, forecast guidance has trended a bit further north with the
    position of a surface low Friday morning. This low is expected to be
    located along the MO River near the SD/IA/NE border, and will
    develop northeast into northern WI/MI U.P. by late afternoon. A
    trailing cold front will push southeast across Upper MS/Mid-MO
    Valley as this occur, becoming oriented from central MI to northwest
    MO and southeast KS by 00z. Meanwhile, a second low is forecast to
    develop over the TX Panhandle/western OK within strong heating near
    a dryline extending southwest from western OK into
    west-central/western TX. Ahead of these surface features, a
    seasonally moist airmass will be in place, or, in the case of the
    Upper Midwest, rapidly advect northward during the morning hours.

    A plume of steep midlevel lapse rates, supported by cool to cold
    temperatures aloft (near -16 C at 500 MB across portions of IA/MN/WI
    at 21z, and -14 to -12 C further southwest) will overspread the
    moist boundary layer. This will result in strong destabilization,
    with MLCAPE around 2500-3500 J/kg expected across the warm sector.
    This kinematic and thermodynamic environment will support robust
    convective development near the Upper Midwest surface low
    southwestward along the cold front into KS by midday. Initial
    supercells are possible, especially closer to the surface low in the
    Upper Midwest, and near the triple point/dryline in northwest
    OK/south-central KS. More rapid upscale growth into a robust
    line/LEWP is expected along the cold front from parts of IA into MO
    and eastern KS. Given robust instability and very steep lapse rates, significant damaging wind swaths will be possible. Additionally,
    large to very large hail will be possible with any discrete
    supercells, and possibly within line-embedded supercells. Low-level
    wind profiles will also support a aerially extensive tornado risk,
    both with QLCS mesovortex circulations, and with discrete
    supercells. A corridor of perhaps greater tornado risk/coverage may
    develop near the surface low from northeast IA into central WI.
    Low-level SRH will be maximized in this area and forecast soundings
    indicate large, curved hodographs becoming elongated above 2-3 km.
    Furthermore, mixing ratios near 14 g/kg and very steep lapse rates
    should support robust updrafts with low cloud bases. This are may
    become a focused corridor for stronger tornadoes.

    Linear convection should continue east across the MS River and Lake
    Michigan during the evening and overnight hours, with a gradually
    waning severe risk into portions of central/southern IL, Lower MI
    and IN. Additional convection may develop during the evening and/or
    overnight across parts of TX near the dryline, though this scenario
    is more conditional. If storms do develop, large will be the main
    risk.

    ..Leitman.. 04/16/2026

    $$

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  • From COD Weather Processor@1:2320/107 to [email protected] on Thu Apr 16 17:43:42 2026
    ACUS02 KWNS 161743
    SWODY2
    SPC AC 161741

    Day 2 Convective Outlook
    NWS Storm Prediction Center Norman OK
    1241 PM CDT Thu Apr 16 2026

    Valid 171200Z - 181200Z

    ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS EXTENDING FROM
    WISCONSIN SOUTHWESTWARD INTO OKLAHOMA...

    ...SUMMARY...
    Widespread severe thunderstorms are expected from parts of the
    southern Plains to the Middle and Upper Mississippi Valley vicinity
    Friday into Friday night. Tornadoes, possibly strong, very large
    hail, and swaths of damaging winds will be possible.

    ...Synopsis...
    An upper trough will move into the central and northern Plains
    during the day, strengthening through Friday night as it moves into
    upper MS Valley. Continuous height falls will occur across the
    entire central to northern Plains region, where mid and upper level temperatures will already be relatively cool.

    During the afternoon, low pressure will develop across IA and WI,
    with a cold front extending southwestward into southern KS and
    northwest OK. A warm front will also lift across IA and into WI
    during the day, with an influx of mid 60s F dewpoints. Given the
    cool temperatures aloft, this will create a highly unstable air mass
    ahead of the cold front. This front will accelerate during the
    evening as storms become numerous, and should extend roughly from
    Lower MI into central TX by 12Z Saturday.

    The combination of steep lapse rates aloft, ample shear, and ample
    moisture will support corridors of significant severe storms,
    including all modes of severe.

    ...From IA into WI and northwest IL...
    Strong tornado potential is evident Friday afternoon into early
    evening, especially from IA into southern WI and northwest IL. While
    convective evolution is a bit uncertain, there is good agreement in
    a very unstable environment with midlevel lapse rates to 8.5 C/km,
    along with 200-300 m2/s2 effective SRH ahead of the surface low and
    near the warm front. While an eventual squall line may take shape
    late in the day, scattered supercells appear likely after about 19Z
    ahead of the developing low and as dewpoints rise rapidly. As such,
    conditional tornado probabilities have been increased further to
    indicate stronger tornado potential.

    Cells should eventually consolidate as the front pushed east, with
    damaging bowing structures expected, possibly as far east as Lake
    MI. The severe risk is expected to persist as far east as IN and
    lower MI late evening/overnight as the southerly low-level jet
    brings moisture northward. Damaging winds appear possible.

    ...OK/KS/MO...
    A volatile environment will develop near and ahead of the cold front
    Friday afternoon, with significant severe hail, wind, and several
    tornadoes expected. An impressive combination of deep-layer
    shear/wind fields and steep lapse rates aloft will exist, and while
    the forcing mechanism will be linear, shear vector orientation and
    likely rightward-propagation of the stronger supercells will support
    tornadoes and very large damaging hail initially. All this activity
    is expected to merge into a linear MCS, with corridors of
    destructive winds and continued large hail risk expected over much
    of MO and into northern OK through the evening.

    ..Jewell.. 04/16/2026

    $$

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  • From COD Weather Processor@1:2320/107 to [email protected] on Fri Apr 17 05:26:45 2026
    ACUS02 KWNS 170526
    SWODY2
    SPC AC 170525

    Day 2 Convective Outlook
    NWS Storm Prediction Center Norman OK
    1225 AM CDT Fri Apr 17 2026

    Valid 181200Z - 191200Z

    ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
    THE UPPER OHIO RIVER VALLEY....

    ...SUMMARY...
    Scattered strong to severe thunderstorms capable of damaging winds
    and hail will be possible on Saturday across the upper Ohio Valley.

    ...Synopsis...
    A mid-level trough will move from the Upper Midwest to the Great
    Lakes on Friday. A surface cold front will move from the Great
    Lakes/Ohio Valley to the Appalachians. In its wake, high pressure
    will build into the Intermountain West and Plains.

    Remnant showers/storms will likely be ongoing at the beginning of
    the period ahead of the cold front. The extensive cloudcover and
    potential outflow from Day 1 storms has resulted in considerable
    uncertainty for the Saturday forecast. Most 00Z guidance shows
    extensive outflow moving across Ohio during the morning. If this
    occurs, additional storm development is not anticipated until
    farther east across western Pennsylvania and southwest New York. If
    these morning storms/outflow are less progressive, some moisture
    advection ahead of the cold front is expected to bring somewhat
    greater instability. This could result in some stronger storms, and
    potentially sufficient instability for some transient supercell
    structures.

    Some 00Z CAM guidance (NAM/NSSL WRF) depicts low to mid 60s
    dewpoints across eastern Ohio and western Pennsylvania on Saturday
    afternoon. This seems to be the outlier, but if this does occur, a
    more substantial severe weather threat, and a greater tornado threat
    would exist across western Pennsylvania into southwest New York.
    However, only weak instability seems most likely within this zone of
    strong shear and therefore, expect damaging wind gusts as the
    primary hazard.

    ..Bentley.. 04/17/2026

    $$

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  • From COD Weather Processor@1:2320/107 to [email protected] on Fri Apr 17 17:32:19 2026
    ACUS02 KWNS 171732
    SWODY2
    SPC AC 171730

    Day 2 Convective Outlook
    NWS Storm Prediction Center Norman OK
    1230 PM CDT Fri Apr 17 2026

    Valid 181200Z - 191200Z

    ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
    THE UPPER OHIO VALLEY AND CENTRAL APPALACHIANS...

    ...SUMMARY...
    Scattered strong to severe thunderstorms capable of damaging winds
    and hail will be possible on Saturday across the upper Ohio Valley
    and central Appalachians. Isolated severe hail is also possible
    across parts of central Texas.

    ...Synopsis...
    An amplified midlevel trough will advance eastward from the upper MS
    Valley to the Great Lakes/OH Valley on Saturday. At the same time, a
    cold front extending from lower MI south-southwestward into
    south-central TX will move east-southeastward across the OH, TN, and
    lower MS Valley during the day. Remnant showers and thunderstorms
    will be ongoing along the eastward-moving front at the start of the
    period, though this lingering/early-morning activity is generally
    expected to be sub-severe.

    ...Upper OH Valley and Central Appalachians...
    As the cold front continues eastward into the upper OH Valley and
    central Appalachians into the afternoon, diurnal heating amid a
    narrow corridor of upper 50s to lower 60s dewpoints will contribute
    to marginal surface-based destabilization immediately ahead of the
    front. This, combined with around 40-50 kt of effective shear
    oriented oblique to the front, should favor a mix of organized
    clusters and perhaps a couple supercell structures -- posing a risk
    of scattered damaging wind gusts and isolated severe hail.
    Additionally, a remnant 30-40 kt south-southwesterly low-level jet
    will yield modest low-level shear/hodograph curvature, and a tornado
    or two will be possible with the more organized storms.

    ...Central TX...
    High-resolution guidance is in relatively good agreement, depicting
    elevated thunderstorms evolving behind the cold front during the
    morning and early afternoon. Steep midlevel lapse rates atop the
    frontal surface and elongated/straight hodographs (around 50 kt of
    effective shear) could lead to isolated severe hail with any
    elevated supercells that evolve.

    ...Lower MS and TN Valleys...
    A couple strong storms will also be possible immediately ahead of
    the front as it impinges on the lower MS and TN Valleys during the
    afternoon, given around 40 kt of deep-layer shear and a weakly
    unstable air mass. However, displacement from the deep-layer forcing
    for ascent accompanying the trough, and skinny CAPE profiles, limits
    confidence in the severe risk here -- precluding probabilities at
    this time.

    ..Weinman.. 04/17/2026

    $$

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  • From COD Weather Processor@1:2320/107 to [email protected] on Sat Apr 18 05:41:26 2026
    ACUS02 KWNS 180541
    SWODY2
    SPC AC 180539

    Day 2 Convective Outlook
    NWS Storm Prediction Center Norman OK
    1239 AM CDT Sat Apr 18 2026

    Valid 191200Z - 201200Z

    ...NO SEVERE THUNDERSTORM AREAS FORECAST...

    ...SUMMARY...
    Severe thunderstorms are not expected on Sunday.

    ...Synopsis...
    A strong mid-level trough will move slowly east from the Great Lakes
    to the Northeast on Sunday. At the surface, a large area of high
    pressure will extend from the Plains to the Midwest and Southeast.
    This will help advance the cold front (and richer moisture) into the
    Atlantic and the Gulf.

    The prevalence of high pressure and a continental, dry airmass
    across most of the country will lead to minimal thunderstorm chances
    on Sunday. A few isolated thunderstorms could develop along the
    front from eastern Georgia to eastern North Carolina before the
    front moves offshore. Scattered thunderstorms are possible along the
    eastern shore of the Florida Peninsula, but given the weak
    instability, strong to severe concern remains minimal.

    Finally, thunderstorms that form over the higher terrain in northern
    Mexico on Sunday may move into parts of South Texas and the Edwards
    Plateau before weakening in the increasingly hostile post-frontal
    environment.

    ..Bentley.. 04/18/2026

    $$

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  • From COD Weather Processor@1:2320/107 to [email protected] on Sat Apr 18 17:25:02 2026
    ACUS02 KWNS 181724
    SWODY2
    SPC AC 181723

    Day 2 Convective Outlook
    NWS Storm Prediction Center Norman OK
    1223 PM CDT Sat Apr 18 2026

    Valid 191200Z - 201200Z

    ...NO SEVERE THUNDERSTORM AREAS FORECAST...

    ...SUMMARY...
    Severe thunderstorms are not expected on Sunday.

    ...Discussion...
    An amplified midlevel trough will move eastward from the Great Lakes
    into the Northeast on Sunday, while a related cold front moves off
    the Eastern Seaboard and the FL Peninsula. Preceding the trough,
    large-scale ascent will support isolated/elevated thunderstorms
    across coastal New England into the afternoon. Similarly, a couple thunderstorms are possible ahead of the front over coastal NC and
    farther south over the central/southern FL Peninsula (aided by an
    Atlantic sea breeze), though much of this activity may develop
    offshore. Farther west over the lower Great Lakes, lapse rates will
    quickly steepen beneath the core of the midlevel trough, and
    sufficient (albeit weak) buoyancy will support a couple
    thunderstorms -- given increasing ascent in the left-exit region of
    a midlevel jet.

    Finally, isolated/elevated thunderstorms will be possible within a
    post-frontal air mass across southwest TX, where weak warm-air
    advection will develop amid modestly steep midlevel lapse rates.

    ..Weinman.. 04/18/2026

    $$

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  • From COD Weather Processor@1:2320/107 to [email protected] on Sun Apr 19 05:48:04 2026
    ACUS02 KWNS 190547
    SWODY2
    SPC AC 190546

    Day 2 Convective Outlook
    NWS Storm Prediction Center Norman OK
    1246 AM CDT Sun Apr 19 2026

    Valid 201200Z - 211200Z

    ...NO SEVERE THUNDERSTORM AREAS FORECAST...

    ...SUMMARY...
    Severe storms are not expected on Monday.

    ... Synopsis ...

    A midlevel trough will progress from the Northeast off the New
    England coast on Monday, while the trailing cold front continues
    southward into the Caribbean Sea. In the wake of this system, high
    pressure and a relatively dry airmass will limit thunderstorm
    potential across much of the CONUS.

    ... South Florida ...

    North of the aforementioned front, diurnal heating of a moist
    post-frontal airmass characterized by dewpoints in the mid-60s
    should support isolated to widely scattered thunderstorms. Weak
    buoyancy and a lack of significant large-scale ascent should
    preclude any severe threat.

    ... Southwest into Texas ...

    Farther west, a subtle, low-amplitude midlevel wave moving into
    South Texas, combined with weak low-level warm advection and modest
    moisture return will support a few rounds of isolated thunderstorms
    across Southwest Texas into Central Texas.

    Additionally, isolated diurnal thunderstorms are possible across the
    Southwest as midlevel moisture impinges on the region. This activity
    is expected to remain focused over the higher terrain, and given the
    weak instability and modest forcing, severe weather is not expected.

    ..Marsh.. 04/19/2026

    $$

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  • From COD Weather Processor@1:2320/107 to [email protected] on Sun Apr 19 17:22:34 2026
    ACUS02 KWNS 191722
    SWODY2
    SPC AC 191720

    Day 2 Convective Outlook
    NWS Storm Prediction Center Norman OK
    1220 PM CDT Sun Apr 19 2026

    Valid 201200Z - 211200Z

    ...NO SEVERE THUNDERSTORM AREAS FORECAST...

    ...SUMMARY...
    Severe storms are not expected on Monday.

    ...Synopsis...
    An upper trough within the Northeast will progress offshore on
    Monday. A subtle shortwave trough within the subtropical jet will
    move into South Texas/middle Texas coast overnight into Tuesday
    morning. On the West Coast, a stronger upper trough will into parts
    of the Northwest and northern/central California. A surface high
    pressure system across much of the east will remain largely in
    place. Very modest moisture return is possible into the Rio Grande
    Valley and Permian Basin/Trans-Pecos regions.

    ...South Florida...
    Moderate mid-level flow is expected across the Peninsula given the
    upper trough to the north. Though mid-level temperatures will be
    cooling during the day, persistent northeasterly winds at the
    surface will lead to a large down-peninsular component at low
    levels. Dewpoints will have a tendency to drop during the same time
    frame. This pattern, coupled with poor mid-level lapse rates, should
    keep severe potential low.

    ...Trans-Pecos into Central/South Texas...
    With moisture return into the Davis Mountains vicinity, a storm or
    two could develop within the terrain. A modest enhancement to
    deep-layer shear in association with the subtle perturbation moving
    through could allow for a stronger storm. Given how isolated this
    activity would be as well as its dependency on sufficient moisture
    return, confidence in such a scenario is quite low.

    Farther east, warm air advection will increase during the overnight
    hours. Elevated buoyancy is expected to increase during this time
    frame. Shear will be weaker with northern extent and increasing
    southward in closer proximity to the weak shortwave perturbation.
    Mid-level lapse rates will be weak as will MUCAPE (less than 750
    J/kg). Small hail may occur with the strongest storms.

    ..Wendt.. 04/19/2026

    $$

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  • From COD Weather Processor@1:2320/107 to [email protected] on Mon Apr 20 05:49:07 2026
    ACUS02 KWNS 200549
    SWODY2
    SPC AC 200547

    Day 2 Convective Outlook
    NWS Storm Prediction Center Norman OK
    1247 AM CDT Mon Apr 20 2026

    Valid 211200Z - 221200Z

    ...NO SEVERE THUNDERSTORM AREAS FORECAST...

    ...SUMMARY...
    Thunderstorms will be possible across the western CONUS, the
    south-central CONUS, and the southern Great Lakes on Tuesday.
    Potential for severe weather appears low.

    ... Synopsis ...

    Midlevel ridging will be in place from the eastern Great Basin into
    the Plains at the start of the forecast period, while persistent
    northwesterly flow aloft continues across the Upper Midwest and Ohio
    Valley. Farther west, an upper trough will gradually advanced inland
    across California into the Great Basin by the end of the period.

    At the surface, a broad area of high pressure centered over the
    Southeast and adjacent Atlantic will maintain southerly flow across
    the central US. This will promote a gradual moisture recovery across
    the central Plains into the southern Great Lakes. A weak frontal
    boundary pushing south through portions of the central Plains and
    Great Lakes will denote the northern edge of the moisture return.

    ... Lower Great Lakes ...

    Thunderstorm development along the frontal zone may be delayed until
    later in the day or evening as moisture slowly returns northward.
    While relatively cold temperatures aloft should support steep lapse
    rates, the quality and depth of the boundary-layer moisture is
    expected to be the biggest unknown. The NAM is the most aggressive
    with the depth and quality of the moisture return, and if moisture
    quality is close to what is shown in the NAM, enough instability
    should materialize to take advantage of the stronger vertical shear
    to support a few organized cells capable of gusty winds or small
    hail. However, most model guidance is less aggressive with the
    quality of the moisture return so no probabilities have been added
    at this time.

    ... South-central US ...

    Convection will likely be ongoing at the start of the forecast
    period. Modest vertical shear and elevated instability may support a
    couple strong thunderstorms capable of hail and gusty winds.
    However, overall thunderstorm intensity should wane through much of
    the period as upper ridging overspreads the region.

    ... Western US ...

    As the upper trough moves inland, ascent will increase across the
    Pacific Northwest, northern California, and portions of the Great
    Basin. Within the Central Valley and nearby terrain, pockets of
    diurnal heating, combined with cool midlevel temperatures may
    support isolated thunderstorm development during the afternoon.
    Despite this modest instability, weak vertical shear should limit
    any organized severe potential.

    ..Marsh.. 04/20/2026

    $$

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  • From COD Weather Processor@1:2320/107 to [email protected] on Mon Apr 20 17:30:37 2026
    ACUS02 KWNS 201726
    SWODY2
    SPC AC 201724

    Day 2 Convective Outlook
    NWS Storm Prediction Center Norman OK
    1224 PM CDT Mon Apr 20 2026

    Valid 211200Z - 221200Z

    ...NO SEVERE THUNDERSTORM AREAS FORECAST...

    ...SUMMARY...
    Thunderstorms will be possible across the West, portions of the
    southern Plains, and the southern Great Lakes on Tuesday. Potential
    for severe weather appears low.

    ...Synopsis...
    Upper-level ridging is expected to build into the Plains on Tuesday.
    Moderate northwesterly flow aloft will remain across the Upper
    Midwest/Great Lakes. In the West, an upper trough will move into
    California and the western Great Basin. At the surface, a high
    pressure system will persist in the Southeast. Initial moisture
    return around the western flank of this anticyclone will occur
    through the day. This moisture will interact with a weak boundary
    within the Midwest/Lower Great Lakes.

    ...Midwest/Lower Great Lakes...
    Ahead of the weak surface boundary, some increase in low-level
    moisture can be expected. Moisture should generally be greater along
    the Iowa/Missouri border with diminishing dewpoints towards the
    Lower Great Lakes/Ohio Valley. Within moderate northwesterly flow
    aloft, a subtle shortwave trough is expected to move towards
    southern Lake Michigan during the afternoon. Temperatures at 500 mb
    of around -18C should promote some convection along the boundary by
    late afternoon. Farther west, forcing for ascent will be weaker and
    capping will be stronger. The main question in this scenario
    continues to be the quantity of moisture return ahead of the
    boundary. Guidance does suggest low 50s F are possible, but given
    how dry the current airmass across the region is and how late this
    initial moisture return will be, confidence in that forecast is low.
    The current expectation is that isolated to widely scattered storms
    are possible by late afternoon/early evening, particularly near
    southern Lake Michigan. These storms may briefly strengthen and be
    capable of gusty winds/small hail. Thereafter, nocturnal cooling
    should lead to a weakening trend. Development near the Iowa/Missouri
    is far more conditional.

    ...Trans-Pecos/Big Bend into Central Texas...
    Convection will be ongoing Tuesday morning in central Texas.
    Isolated small hail and gusty winds are possible, but deep-layer
    shear will be weakening as the ridge builds into the Plains through
    the day. Farther west, a weak dryline is possible into the Big Bend
    region. An isolated storm or two could develop. Weak vertical shear
    and marginal buoyancy should limit severe potential.

    ...California Central Valley...
    After an initial period of precipitation in the morning, pockets of
    surface heating in the afternoon may lead to MLCAPE of 250-500 J/kg.
    While a stronger storm or two is possible, the severe threat will be
    limited by weak deep-layer shear.

    ..Wendt.. 04/20/2026

    $$

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  • From COD Weather Processor@1:2320/107 to [email protected] on Tue Apr 21 05:54:46 2026
    ACUS02 KWNS 210554
    SWODY2
    SPC AC 210553

    Day 2 Convective Outlook
    NWS Storm Prediction Center Norman OK
    1253 AM CDT Tue Apr 21 2026

    Valid 221200Z - 231200Z

    ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS
    OF THE HIGH PLAINS...

    ...SUMMARY...
    Severe thunderstorms capable of hail and gusty winds may develop
    during the late afternoon and evening on Wednesday across portions
    of the High Plains.

    ... Synopsis ...

    A closed upper low across the western US will devolve into an open
    wave as it lifts northeast toward the northern Plains. At the same
    time, a surface low will gradually deepen as it moves across
    northern Montana east into North Dakota by Thursday morning.

    Lee troughing will strengthen during the day with the approach of
    the western trough. The surface wind field within this lee trough
    will function to sharpen a dryline from the surface low south across
    much of the High Plains. To the east of the dryline, strengthening
    southerly winds will draw Gulf moisture northward into the
    strengthening cyclone. The quality of this moisture return remains a significant source of uncertainty regarding thunderstorm chances
    with northward extent.

    ... Northern High Plains including areas of eastern Montana...

    By late afternoon increasing large-scale ascent, driven by modest
    height falls, will overspread northern portions of the dryline.
    Despite moisture concerns, isolated to scattered thunderstorms
    should develop across portions of the dryline during the afternoon.
    Large temperature/dewpoint spreads may support strong wind gusts
    with the strongest storms.

    The best synoptic scale forcing for ascent will move across portions
    of eastern Montana during the late afternoon and evening. Should
    boundary layer moisture be richer than currently anticipated (e.g.,
    closer to 40F than 25F), a threat for marginally severe wind gusts
    may materialize. This area will continued to be assessed in
    subsequent outlooks for an upgrade to Level 1/Marginal.

    ... Southern High Plains ...

    Midlevel height falls will not be as great here as compared to areas
    farther north. However, richer boundary layer moisture and strong
    dryline circulations aided by temperatures approaching 90F to the
    west of the dryline should support at least isolated thunderstorm
    development. Around 40 knots of cloud-layer shear should support at
    least a marginal hail risk with any storm that develops.

    ..Marsh.. 04/21/2026

    $$

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  • From COD Weather Processor@1:2320/107 to [email protected] on Tue Apr 21 17:26:18 2026
    ACUS02 KWNS 211726
    SWODY2
    SPC AC 211724

    Day 2 Convective Outlook
    NWS Storm Prediction Center Norman OK
    1224 PM CDT Tue Apr 21 2026

    Valid 221200Z - 231200Z

    ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE
    HIGH PLAINS...

    ...SUMMARY...
    Severe thunderstorms capable of hail and gusty winds may develop
    during the late afternoon and evening on Wednesday across portions
    of the High Plains.

    ...Synopsis...
    A broad trough within parts of the Northwest and Great Basin will
    progress eastward through the day Wednesday. The mid-level jet will
    round the base of this trough and impact the northern High Plains
    during the evening overnight. A secondary mid-level jet will dig
    into the Southwest by early Thursday morning. The upper-level ridge
    across the Plains will begin to break down and shift eastward. At
    the surface, a deep surface low will track along the Montana/Canada
    border. Strengthening flow across the Rockies will promote a
    moderately strong lee trough. Surface moisture will continue to
    advect north and west during the period. Richer moisture will
    generally remain within the southern Plains and adjacent High Plains
    with less certain moisture quality farther north.

    ...Western Nebraska...western South Dakota...
    With greater large-scale ascent and closer proximity to the surface
    low, confidence in storm development is higher in these areas. The
    main question will be the degree of moisture return that can occur
    through the day. Model guidance still varies widely in this regard.
    Dewpoints near 50 F are possible into southwest Nebraska, but this
    may occur towards 00Z or later. Farther north, dewpoints in the 40s
    F may be the ceiling for late afternoon/early evening. A probable
    scenario is that high-based convection develops within the terrain
    of eastern Wyoming/western South Dakota and within the surface
    trough. Some intensification is possible as this activity encounters
    greater surface moisture to the east. Severe wind gusts will be the
    main hazard given the steep low-level lapse rates and inverted-v
    thermodynamic profiles. Linear structures would be favored in South
    Dakota given the deep-layer flow orientation. A supercell or two
    could occur in western Nebraska, should storms form.

    ...Southern High Plains into Western Kansas...
    With the synoptic trough lagging to the west, mid-level height falls
    will be very weak during the afternoon. The dryline/surface trough
    will be the focus for storm development. Temperatures nearing 90 F
    behind the dryline appear sufficient for an isolated storm or two to
    develop. That said, some guidance does not develop any convection.
    Deep-layer shear will be roughly perpendicular to the surface trough
    and mid-level lapse rates will be steep. Storms that can develop
    will be supercellular. Large hail would be the main concern with
    this activity.

    ...Eastern Montana...
    High-based convection is possible in association with the deepening
    surface low. Dewpoints will not likely reach 40 F. Gusty outflow
    winds are possible, but potential for severe gusts is low.

    ..Wendt.. 04/21/2026

    $$

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  • From COD Weather Processor@1:2320/107 to [email protected] on Wed Apr 22 06:01:54 2026
    ACUS02 KWNS 220601
    SWODY2
    SPC AC 220600

    Day 2 Convective Outlook
    NWS Storm Prediction Center Norman OK
    0100 AM CDT Wed Apr 22 2026

    Valid 231200Z - 241200Z

    ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM SOUTHERN
    KANSAS INTO SOUTHERN MINNESOTA...

    ...SUMMARY...
    Severe thunderstorms will be possible from southern Kansas into
    southern Minnesota on Thursday. Large hail to very large hail,
    damaging winds, and a few tornadoes are possible.

    ... Synopsis ...

    A shortwave trough will move northeast along the eastern periphery
    of a western US longwave trough. This shortwave will help maintain a
    surface cyclone in southern Canada, while a secondary surface low
    may develop across southern Minnesota late in the period. A
    secondary shortwave will approach the southern Plains late in the
    forecast period.

    As the shortwave trough lifts northeast, a cold front will
    accelerate east across the central and northern Plains. Ahead of the
    surface front southerly winds will support mid 50F dewpoints as far
    north as northern Minnesota and pockets of 60F dewpoints perhaps as
    far north as southern-to-central Minnesota.

    ... Central and Northern Plains ...

    Diurnal heating of the moist airmass ahead of the advancing surface
    front will yield an increasingly unstable atmosphere during the
    afternoon with the 20260422/00Z HREF showing ensemble mean SBCAPE
    values approaching 2000 J/kg as far north as the greater Omaha, NE,
    vicinity by 20Z. Interrogation of forecast soundings ahead of the
    frontal boundary shows a strong cap stretching from Oklahoma
    northward into Nebraska and Iowa. This cap does lift during the day
    in response to increasing large-scale ascent from the approaching
    trough, but thunderstorm initiation will likely require convergence
    along the surface front.

    This should occur by mid-afternoon anywhere from northeast Kansas
    into southern Minnesota. Initially, deep-layer shear is not
    particularly strong across the warm sector, but would still support
    a combination of multi-cells and supercells. Given the degree of
    instability and steep midlevel lapse rates, large-to-very-large hail
    would be possible with any of these initial storms. A tornado or two
    would also be possible given some low-level curvature in the
    forecast hodographs associated with at least a modest low-level jet.


    As the cold front continues to move east into the moist and unstable
    airmass, additional thunderstorms should develop along the front,
    eventually growing upscale into one or more linear systems and a
    transition to a damaging wind threat. Vertical shear should improve
    during the late afternoon and evening as the mid-to-upper-level
    winds respond to the approach trough, yielding a continued tornado
    threat with any persistent discrete cell.

    ... Oklahoma and Northwest Texas ...

    A very unstable airmass will develop across the region to the east
    of a dryline across western Oklahoma during the afternoon. Forecast
    soundings show varying degrees of a cap across Oklahoma and
    Northwest Texas. With the strongest large-scale ascent remaining
    largely to the north of the area, forcing for ascent will likely
    require strong dryline circulations. Given afternoon temperatures in
    the 90Fs to the west of the dryline, there is at least some
    potential for dryline circulations to break the cap and initiate at
    least a couple of storms. Vertical shear profiles will support
    supercells capable of very large hail. A highly conditional tornado
    threat could develop with any discrete storm that is able to move
    off the dryline and into the increasingly moist and unstable
    environment to the east.

    ..Marsh.. 04/22/2026

    $$

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  • From COD Weather Processor@1:2320/107 to [email protected] on Wed Apr 22 17:24:27 2026
    ACUS02 KWNS 221724
    SWODY2
    SPC AC 221722

    Day 2 Convective Outlook
    NWS Storm Prediction Center Norman OK
    1222 PM CDT Wed Apr 22 2026

    Valid 231200Z - 241200Z

    ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM SOUTHERN
    KANSAS INTO SOUTHERN MINNESOTA...

    ...SUMMARY...
    Severe thunderstorms will be possible from southern Kansas into
    southern Minnesota on Thursday. Large hail to very large hail,
    damaging winds, and a few tornadoes are possible.

    ...Synopsis...

    A short-wave trough initially over the northern High Plains Thursday
    morning is forecast to shift east across the northern Plains into
    the upper MS Valley in tandem with a belt of 50-60 kt
    south-southwest winds in the mid levels. A secondary, lower-latitude disturbance will advance into western KS and the OK/TX panhandles
    late Thursday afternoon into evening, along with a more zonal
    mid/upper-level jet streak. At the surface, the primary cyclone
    attendant to the northern Plains system is expected to undergo
    occlusion over southern into central Manitoba, while a trailing cold
    front progresses east through the northern Plains into the upper MS
    Valley. A pre-frontal trough or pseudo-dryline will precede the cold
    front, extending from western MN through western IA and eastern NE
    into central KS by early to mid afternoon. A secondary surface low
    is forecast to deepen across portions of southwest KS or northwest
    OK Thursday afternoon in response to the approach of the
    lower-latitude disturbance mentioned above. A more classic dryline
    will extend south from that low through western OK into western
    north TX during the peak of the diurnal heating cycle.

    ...Upper MS Valley and upper Midwest through the mid/lower MO Valley
    into central/eastern KS...

    A broad, nocturnal, low-level wind maximum will develop across the
    Great Plains tonight (Wed. night), enhancing the poleward flux of an increasingly moist boundary layer beneath a residual EML plume
    residing across the same region. The moisture increase beneath a
    capping inversion at the base of the EML may result in considerable
    cloud cover Thursday afternoon across portions of the warm sector
    air mass. Where cloud breaks occur, model soundings indicate the
    potential for MLCAPE to approach 1000-1500 J/kg across portions of
    southern MN to as high as 2000-3000+ J/kg in central and eastern KS.

    By early to mid afternoon, convergence along the pre-frontal
    trough/dryline coupled with increasing height falls/forcing for
    ascent are expected to support widely scattered thunderstorms from
    portions of central and southern MN through eastern NE and western
    IA, into at least northeast KS. While the strongest mid/upper-level
    wind fields are expected to remain to the immediate west of the
    initiating boundary, a corridor of 40-45 kt effective bulk shear
    will overlie the western fringe of the warm sector, supporting
    organized multicells and supercells as the initial storm mode with
    an attendant threat for large to very large hail and a few
    tornadoes. Subsequent upscale growth into a broken band of storms is
    expected Thursday evening into Thursday night across portions of
    eastern MN into western WI, western and central IA, southeast NE,
    northeast KS, and northwest MO. Damaging wind potential will
    increase with that mode change, with a continued risk for a few
    tornadoes.

    The most favorable overlap of moderate to strong instability and
    vertical wind shear is expected to develop across central into
    eastern KS Thursday afternoon into evening. Here, a few intense
    supercells capable of all severe-weather hazards appear possible,
    and a categorical upgrade to a level 3/Enhanced Risk may be required
    in subsequent Day 1 outlooks.

    ...OK into north TX...

    Moderate to strong instability (MLCAPE of 2500-3500 J/kg) is
    expected to develop east of the dryline by late afternoon into early
    evening on Thursday. However, strong capping at the base of the EML
    casts considerable uncertainty on whether storms can develop. While
    the strongest forcing for ascent associated with the secondary
    short-wave trough is expected to remain across KS, subtle mid-level
    height falls are forecast across northern OK. Otherwise, strong
    heating to the west of the dryline and resultant deepening
    circulations along it will be the primary mechanism responsible for
    any storm development.

    On the condition that isolated storms develop and become sustained,
    the kinematic environment will support supercells capable of very
    large hail and tornadoes. This is especially the case during the
    evening hours as low-level shear strengthens in response to the
    amplification of the low-level jet.

    ..Mead.. 04/22/2026

    $$

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  • From COD Weather Processor@1:2320/107 to [email protected] on Thu Apr 23 06:02:04 2026
    ACUS02 KWNS 230601
    SWODY2
    SPC AC 230600

    Day 2 Convective Outlook
    NWS Storm Prediction Center Norman OK
    0100 AM CDT Thu Apr 23 2026

    Valid 241200Z - 251200Z

    ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS PARTS OF THE
    SOUTHERN PLAINS INTO THE LOWER MISSISSIPPI VALLEY...

    ...SUMMARY...
    Scatteed severe thunderstorms are possible Friday from the Southern
    Plains into the Lower Mississippi Valley. Large hail and damaging
    winds will be the main hazards, with a brief tornado also possible.
    Isolated strong wind gusts may occur across portions of the lower
    Ohio Valley as well.

    ... Synopsis ...

    Broad cyclonic flow will persist across much of the central and
    western US as a longwave trough remains anchored over the northern
    states. In the absences of stronger large-scale ascent across the
    southern US, convective evolution will be driven primarily by
    remnant boundaries and subtle perturbations within the broader
    cyclonic flow.

    ... Southern Plains into the Lower Mississippi Valley ...

    Convection is expected to be ongoing from portions of Oklahoma into
    Arkansas and Missouri at the start of the forecast period, largely
    tied to a convectively augmented cold front. This activity may still
    be capable of producing isolated strong wind gusts early in the
    period, but should gradually weaken through the morning as the
    low-level jet dissipates and the parent shortwave trough moves away
    from the region.

    The primary severe threat is expected to develop from afternoon into
    the evening along the effective frontal zone and any residual
    outflow or differential heating boundaries. Current guidance
    suggests the boundary will settle near or south of the I-40
    corridor, though some uncertainty in the exact location remains.
    Notably, the HRRR is an outlier in maintaining a farther north and
    west boundary as compared to other members of the 20260423/00Z HREF.


    By afternoon, strong heating south of the boundary will support a
    moderately to strongly unstable airmass (SBCAPE values in the
    2000-3000 J/kg range) from central/east Texas northward toward the
    boundary, with instability gradually decreasing with eastward extent
    into Mississippi and Alabama. Deep-layer shear will remain modest
    across the region (generally 30-35 knots), supporting organized
    multicells and occasional transient supercells.

    Thunderstorms should develop/intensify from eastern Oklahoma into
    Arkansas along one or more of boundaries across the region. Initial
    storms may pose a threat for large hail and localized damaging wind
    gusts as low-level shear will generally remain weak. However,
    localized enhancements along boundaries or any MCV could support a
    brief tornado risk.

    With time, storm interactions and consolidating outflows should
    support upscale growth into one or more clusters or linear MCS
    structures. These systems should move east-southeast into northern
    Louisiana and central Mississippi through the afternoon and evening
    hours. While the modest deep-layer shear may temper the overall wind
    threat somewhat, sufficient organization should still support a
    corridor of damaging wind gusts.

    Farther west into central and eastern Texas, isolated convection may
    occur along a dryline as diurnal heating weakens inhibition to the
    east. Storm coverage is expected to remain sparse given weak ascent,
    but any sustained updrafts in this strongly unstable environment
    could produce large hail.

    ... Portions of the Ohio Valley ...

    A separate corridor of thunderstorms may develop during the
    afternoon across portions of the eastern Indiana and western Ohio
    in the wake of earlier convection. Modest destabilization should
    occur with perhaps up to 1000 J/kg of SBCAPE. Although the low-level
    jet will be weakening through the day, residual flow and modest
    deep-layer shear may support loosely organized convection capable of
    producing damaging wind gusts.

    ..Marsh.. 04/23/2026

    $$

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  • From COD Weather Processor@1:2320/107 to [email protected] on Thu Apr 23 17:15:43 2026
    ACUS02 KWNS 231715
    SWODY2
    SPC AC 231715

    Day 2 Convective Outlook
    NWS Storm Prediction Center Norman OK
    Issued by 15th OWS Scott Air Force Base IL
    1215 PM CDT Thu Apr 23 2026

    Valid 241200Z - 251200Z

    ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS PARTS OF THE
    SOUTHERN PLAINS INTO THE LOWER MISSISSIPPI VALLEY...

    ...SUMMARY...
    Scattered severe thunderstorms are possible Friday from the Southern
    Plains into the Lower Mississippi Valley. Large hail and damaging
    winds will be the main hazards, with a brief tornado also possible.
    Isolated strong wind gusts may occur across portions of the lower
    Ohio Valley as well.

    ... Synopsis ...

    Broad cyclonic flow will persist across much of the central and
    western US as a longwave trough remains anchored over the northern
    states. In the absences of stronger large-scale ascent across the
    southern US, convective evolution will be driven primarily by
    remnant boundaries and subtle perturbations within the broader
    cyclonic flow.

    ... Southern Plains into the Lower Mississippi Valley ...

    Convection is expected to be ongoing from portions of Oklahoma into
    Arkansas and Missouri at the start of the forecast period, largely
    tied to a convectively augmented cold front. This activity may still
    be capable of producing isolated strong wind gusts early in the
    period, but should gradually weaken through the morning as the
    low-level jet dissipates and the parent shortwave trough moves away
    from the region.

    The primary severe threat is expected to develop from the afternoon
    into the evening along the effective frontal zone and any residual
    outflow or differential heating boundaries. Current guidance
    suggests the boundary will settle near or south of the I-40
    corridor, though some uncertainty in the exact location remains.
    Notably, the HRRR is an outlier in maintaining a farther north and
    west boundary as compared to other members of the 20260423/Z HREF.

    By afternoon, strong heating south of the boundary will support a
    moderately to strongly unstable airmass (SBCAPE values in the
    2000-3000 J/kg range) from central/east Texas northward toward the
    boundary, with instability gradually decreasing with eastward extent
    into Mississippi and Alabama. Deep-layer shear will remain modest
    across the region (generally 30-35 knots), supporting organized
    multicells and occasional transient supercells.

    Thunderstorms should develop/intensify from eastern Oklahoma into
    Arkansas along one or more of boundaries across the region. Initial
    storms may pose a threat for large hail and localized damaging wind
    gusts as low-level shear will generally remain weak. However,
    localized enhancements along boundaries or any MCV could support a
    brief tornado risk.

    With time, storm interactions and consolidating outflows should
    support upscale growth into one or more clusters or linear MCS
    structures. These systems should move east-southeast into northern
    Louisiana and central Mississippi through the afternoon and evening
    hours. While the modest deep-layer shear may temper the overall wind
    threat somewhat, sufficient organization should still support a
    corridor of damaging wind gusts.

    Farther west into central and eastern Texas, isolated convection may
    occur along a dryline as diurnal heating weakens inhibition to the
    east. Storm coverage is expected to remain sparse given weak ascent,
    but any sustained updrafts in this strongly unstable environment
    could produce large hail.

    ... Portions of the Ohio Valley ...

    A separate corridor of thunderstorms may develop during the
    afternoon across portions of the eastern Indiana and western Ohio
    in the wake of earlier convection. Modest destabilization should
    occur with perhaps up to 1000 J/kg of SBCAPE. Although the low-level
    jet will be weakening through the day, residual flow and modest
    deep-layer shear may support loosely organized convection capable of
    producing damaging wind gusts.

    ..Afwa.. 04/23/2026

    $$

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  • From COD Weather Processor@1:2320/107 to [email protected] on Thu Apr 23 17:52:35 2026
    ACUS02 KWNS 231752
    SWODY2
    SPC AC 231715

    Day 2 Convective Outlook
    NWS Storm Prediction Center Norman OK
    Issued by 15th OWS Scott Air Force Base IL
    1215 PM CDT Thu Apr 23 2026

    Valid 241200Z - 251200Z

    ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS PARTS OF THE
    SOUTHERN PLAINS INTO THE LOWER MISSISSIPPI VALLEY...

    ...SUMMARY...
    Scattered severe thunderstorms are possible Friday from the Southern
    Plains into the Lower Mississippi Valley. Large hail and damaging
    winds will be the main hazards, with a brief tornado also possible.
    Isolated strong wind gusts may occur across portions of the lower
    Ohio Valley as well.

    ... Synopsis ...

    Broad cyclonic flow will persist across much of the central and
    western US as a longwave trough remains anchored over the northern
    states. In the absences of stronger large-scale ascent across the
    southern US, convective evolution will be driven primarily by
    remnant boundaries and subtle perturbations within the broader
    cyclonic flow.

    ... Southern Plains into the Lower Mississippi Valley ...

    Convection is expected to be ongoing from portions of Oklahoma into
    Arkansas and Missouri at the start of the forecast period, largely
    tied to a convectively augmented cold front. This activity may still
    be capable of producing isolated strong wind gusts early in the
    period, but should gradually weaken through the morning as the
    low-level jet dissipates and the parent shortwave trough moves away
    from the region.

    The primary severe threat is expected to develop from the afternoon
    into the evening along the effective frontal zone and any residual
    outflow or differential heating boundaries. Current guidance
    suggests the boundary will settle near or south of the I-40
    corridor, though some uncertainty in the exact location remains.
    Notably, the HRRR is an outlier in maintaining a farther north and
    west boundary as compared to other members of the 20260423/Z HREF.

    By afternoon, strong heating south of the boundary will support a
    moderately to strongly unstable airmass (SBCAPE values in the
    2000-3000 J/kg range) from central/east Texas northward toward the
    boundary, with instability gradually decreasing with eastward extent
    into Mississippi and Alabama. Deep-layer shear will remain modest
    across the region (generally 30-35 knots), supporting organized
    multicells and occasional transient supercells.

    Thunderstorms should develop/intensify from eastern Oklahoma into
    Arkansas along one or more of boundaries across the region. Initial
    storms may pose a threat for large hail and localized damaging wind
    gusts as low-level shear will generally remain weak. However,
    localized enhancements along boundaries or any MCV could support a
    brief tornado risk.

    With time, storm interactions and consolidating outflows should
    support upscale growth into one or more clusters or linear MCS
    structures. These systems should move east-southeast into northern
    Louisiana and central Mississippi through the afternoon and evening
    hours. While the modest deep-layer shear may temper the overall wind
    threat somewhat, sufficient organization should still support a
    corridor of damaging wind gusts.

    Farther west into central and eastern Texas, isolated convection may
    occur along a dryline as diurnal heating weakens inhibition to the
    east. Storm coverage is expected to remain sparse given weak ascent,
    but any sustained updrafts in this strongly unstable environment
    could produce large hail.

    ... Portions of the Ohio Valley ...

    A separate corridor of thunderstorms may develop during the
    afternoon across portions of the eastern Indiana and western Ohio
    in the wake of earlier convection. Modest destabilization should
    occur with perhaps up to 1000 J/kg of SBCAPE. Although the low-level
    jet will be weakening through the day, residual flow and modest
    deep-layer shear may support loosely organized convection capable of
    producing damaging wind gusts.

    ..Afwa.. 04/23/2026

    $$

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  • From COD Weather Processor@1:2320/107 to [email protected] on Fri Apr 24 05:35:41 2026
    ACUS02 KWNS 240535
    SWODY2
    SPC AC 240534

    Day 2 Convective Outlook
    NWS Storm Prediction Center Norman OK
    1234 AM CDT Fri Apr 24 2026

    Valid 251200Z - 261200Z

    ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS SATURDAY
    AFTERNOON AND EVENING ACROSS PARTS OF NORTH CENTRAL AND EASTERN OKLAHOMA...ADJACENT PORTIONS OF SOUTHERN KANSAS AND WESTERN
    ARKANSAS...

    ...SUMMARY...
    One or two clusters of strong to severe thunderstorms, posing a risk
    for large hail and damaging wind gusts, are possible across parts of
    the southeastern Great Plains Saturday afternoon and evening.

    ...Discussion...
    Downstream of an initially amplified, but becoming increasingly
    suppressed, blocking ridge, models indicate that the center of a
    deep mid-level low now forming over southern Saskatchewan may only
    move subtly northward or northwestward through this period. It
    appears that the broader cyclonic circulation will continue to
    elongate Saturday through Saturday night, with one notable emerging
    short wave perturbation accelerating north of the international
    border through northwestern Quebec. To the southwest of the
    residual mid-level low, a couple of additional emerging
    perturbations are forecast to contribute to south-southwestward
    digging troughing along and inland of the U.S. Pacific coast.

    In response to the latter development, a fairly significant short
    wave impulse is forecast to accelerate east-northeastward out of the
    southern mid-latitude eastern Pacific, inland of the Pacific coast
    through the southern Great Basin and lower Colorado Valley by 12Z
    Sunday. Downstream, mid-level heights are forecast to generally
    rise with large-scale ridging building across the southern Rockies
    through much of the Great Plains and Mississippi Valley. Models
    continue to suggest that this may be slowed a bit by subtle
    mid-level height falls associated with a weak short wave
    perturbation progressing east of the southern Rockies, through
    portions of Kansas and Oklahoma during the day Saturday.

    In lower levels, seasonably moist air, supportive of moderate to
    strong potential instability beneath steep mid-level lapse rates,
    appears likely to remain confined beneath the larger-scale mid-level
    ridging. Initially this will be south of the Red River through the
    lower Mississippi Valley, along and south of a convectively enhanced
    surface front which may become increasingly diffuse through the day.
    Models vary with the extent to which this occurs across and north
    of the Red River through the Texas/Oklahoma Panhandle vicinity, but
    a dryline is generally forecast to sharpen roughly from the Wichita
    Falls TX through Del Rio TX vicinity by late Saturday afternoon,
    near the southeastern periphery of broad weak surface troughing.

    ...Central/Southern Great Plains...
    Model disparity concerning the evolution of surface boundaries and boundary-layer moistening/destabilization to the north of the Red
    River add uncertainty to this forecast. Stronger mid-level ridging
    and capping will remain present to the south of the Red River, as
    subtle mid-level height falls overspread parts of Kansas/Oklahoma
    through the day.

    At some point, it appears that large-scale forcing for ascent aided
    by lower/mid-tropospheric warm advection will support increasing
    thunderstorm development within elevated moisture return and
    destabilization. Latest convection allowing guidance suggests
    highest probabilities for this to occur may be well to the north and
    east of the dryline, across parts of north central Oklahoma by mid
    to late afternoon, when it appears that at least elevated
    destabilization may support the risk for large hail, perhaps
    occasionally in excess of 2 inches in diameter, in the presence of
    strong cloud-bearing layer shear.

    Even if the near-surface inflow for this activity begins to emanate
    from a more unstable boundary-layer, rather modest to weak low-level
    hodographs probably will limit tornadic potential. However,
    increasing and consolidating convective development could gradually
    organize and become capable of producing strong to severe wind gusts
    late Saturday afternoon and evening, while tending to propagate
    southeastward across eastern Oklahoma and adjacent portions of
    Arkansas.

    ..Kerr.. 04/24/2026

    $$

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  • From COD Weather Processor@1:2320/107 to [email protected] on Fri Apr 24 17:32:16 2026
    ACUS02 KWNS 241732
    SWODY2
    SPC AC 241730

    Day 2 Convective Outlook
    NWS Storm Prediction Center Norman OK
    1230 PM CDT Fri Apr 24 2026

    Valid 251200Z - 261200Z

    ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM
    NORTH-CENTRAL INTO EASTERN OKLAHOMA AND ADJACENT PARTS OF SOUTHEAST
    KANSAS AND WESTERN ARKANSAS...

    ...SUMMARY...
    Severe thunderstorms, with a risk for large to very large hail,
    damaging wind gusts, and a few tornadoes, are possible across parts
    of the southeastern Great Plains into the ArkLaTex, primarily
    Saturday afternoon and evening.

    ...Synopsis...
    A deep mid/upper-level low is forecast to remain nearly stationary
    over the Canadian Prairie region on Saturday. This low will continue
    to anchor a large-scale mid/upper trough covering much of the
    western and central CONUS through the period. A shortwave trough
    initially off of the southern CA coast will move east-northeastward
    toward the Southwest by Sunday morning. Downstream of this system, a low-amplitude midlevel shortwave trough may emerge from the southern
    Rockies and begin to impinge upon a moist and unstable environment
    across the south-central Plains by afternoon.

    At the surface, a surface low is forecast to gradually deepen across
    the TX Panhandle region through the day, with a dryline extending
    southward from this low into parts of west-central and southwest TX.
    An outflow-influenced surface boundary will initially extend
    east-southeast of the low into parts of the Southeast. This boundary
    is forecast to move northward as a warm front through the day across
    parts of OK/north TX into the ArkLaTex region.

    ...Southern/central Plains into the ArkLaTex...
    Relatively steep lapse rates atop a richly moist boundary layer will
    result in moderate to strong destabilization along/east of the
    dryline and near/south of the effective warm front. Details of
    diurnal storm development and coverage remain unclear, but at least
    isolated storm development will be possible near or just to the cool
    side of the effective warm front by late afternoon, as the
    approaching low-amplitude midlevel shortwave trough glances the
    stronger instability. Initial storms across eastern KS/OK may be
    somewhat elevated, but surface-based convection may eventually
    develop near the warm front/dryline intersection and expand in
    coverage into the evening.

    Initial supercell development will pose a threat of large to very
    large hail and localized damaging gusts. Low-level flow/shear will
    generally remain modest, but large instability and enhanced SRH near
    the surface boundary could result in a localized region of greater
    tornado potential. With time, some upscale growth may result in an
    organized storm cluster moving southeastward to the ArkLaTex and
    potentially the lower MS Valley along the primary instability
    gradient. This evolution could be accompanied by increasing
    damaging-wind potential, though embedded supercells may continue to
    pose a localized hail and tornado threat well into the evening.

    Development along the dryline across TX continues to be uncertain,
    since this area will be removed from stronger large-scale ascent.
    However, strong heating and removal of CINH could result in isolated
    supercell development, with an attendant threat of large to very
    large hail, and a nonzero tornado and wind risk.

    Farther north, a separate area of storm development is possible from central/northern KS into southeast NE. While instability and
    deep-layer flow/shear will generally be weaker with northward
    extent, cool temperatures aloft and modest midlevel flow could
    support a threat for isolated hail and strong/damaging gusts with
    the strongest storms during the afternoon and early evening.

    ...Parts of the Southeast into the Carolinas/Virginia...
    A broad area of weak to moderate instability may develop during the
    afternoon from parts of the Southeast into the Carolinas/Virginia,
    near and to the warm side of a weak surface front. Wind profiles
    will be relatively modest, but may support marginally organized
    storms. Guidance continues to vary regarding placement of the
    primary surface boundary and potential for any MCV development from
    late D1/Friday. Low severe probabilities may eventually need to
    expanded across parts of the Southeast, once details become better
    resolved.

    ..Dean.. 04/24/2026

    $$

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  • From COD Weather Processor@1:2320/107 to [email protected] on Sat Apr 25 05:36:48 2026
    ACUS02 KWNS 250536
    SWODY2
    SPC AC 250534

    Day 2 Convective Outlook
    NWS Storm Prediction Center Norman OK
    1234 AM CDT Sat Apr 25 2026

    Valid 261200Z - 271200Z

    ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS LATE SUNDAY
    INTO SUNDAY NIGHT ACROSS MUCH OF CENTRAL AND EASTERN
    KANSAS...ADJACENT PORTIONS OF SOUTHERN NEBRASKA AND WEST CENTRAL
    MISSOURI...

    ...SUMMARY...
    Isolated to widely scattered severe storms with potential to produce
    large hail and a couple of strong tornadoes are possible by early
    Sunday evening across parts of the central and southern Great
    Plains, before one or two organizing clusters of storms spread
    toward the middle/lower Missouri Valley with potentially damaging
    wind gusts.

    ...Discussion...
    Models continue to indicate that a remnant elongated cyclonic
    mid-level circulation will tend to redevelop north-northeastward
    through Saskatchewan/Manitoba during this period, within generally
    weakening larger-scale troughing extending along an axis inland of
    the U.S. Pacific coast through the Hudson Bay vicinity. At the same
    time, mid/upper ridging across southern/central Mexico into portions
    of the southern Great Plains and lower Mississippi Valley appears
    likely to maintain considerable strength, as a notable short wave
    perturbation accelerates out of the southern Great Basin/lower
    Colorado Valley, within southwesterly flow which is likely to
    strengthen across the southern Rockies through central Great Plains
    late Sunday through Sunday night.

    There appears a bit more disparity within guidance concerning when
    the stronger mid-level height falls associated with the primary
    impulse spread across the Rockies through the eastern
    Colorado/western Kansas/southwest Nebraska vicinity of the high
    plains. It now appears that it may not be until early evening or
    later, but it does appear that this may be preceded by a more subtle perturbation across the same vicinity, perhaps as early as Sunday
    morning. The lead wave may be accompanied by one developing surface
    low within lee surface troughing across central Nebraska into the
    mid Missouri Valley, while the trailing wave supports the eastward
    migration of another surface cyclone out of southeastern Colorado
    into central Kansas late Sunday through 12Z Monday.

    In response to these developments, seasonably moist low-level air,
    initially confined to the southern Great Plains, perhaps as far
    north as central Oklahoma at the outset of the period, may tend to
    advect in a corridor ahead of a sharpening dryline across western
    Oklahoma into western Kansas by late afternoon. Downstream, models
    suggest that warm advection, at least in lower/mid-levels, will
    strengthen and become focused in a corridor across north central
    through northeastern Kansas by late Sunday evening, near the nose of
    a plume of warm and more strongly capping elevated mixed-layer air.

    ...Central/Southern Great Plains...
    Latest model output, including convection allowing guidance, has not
    offered much more in the way of clarity concerning convective
    potential for this period. Among other issues, the plume of warm
    elevated mixed-layer air advecting northeastward through the
    southern and central Great Plains may prove inhibitive to the
    initiation of storms across much of the developing warm sector,
    while also contributing to moderate to strong potential instability.
    Potential for early day convection across western Kansas and
    adjacent portions of the high plains may also impact later day
    severe weather potential.

    Even so, guidance generally indicates that a cyclonically curved,
    50-70+ kt 500 mb jet streak will nose across the Texas/Oklahoma
    Panhandle region by early Sunday evening. This likely will
    contribute to strengthening convergence along a sharpening dryline, particularly across portions of western Kansas, where at least a
    narrow corridor of moderate boundary-layer destabilization probably
    will become supportive of supercell development. The potential for
    a couple of strong tornadoes probably will increase as cells
    propagate east-northeastward Sunday evening, in the presence of
    enlarging clockwise curved hodographs beneath a strengthening
    southerly low-level jet (including 40-50+ kt around 850 mb).
    Tornadic potential probably will maximize during the mid to late
    evening, before convection consolidates and grows upscale into one
    or more clusters, in the presence of forcing for ascent aided by
    strengthening lower/mid-tropospheric warm advection across north central/northeastern Kansas and adjacent portions of the Great
    Plains.

    ..Kerr.. 04/25/2026

    $$

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  • From COD Weather Processor@1:2320/107 to [email protected] on Sat Apr 25 17:35:50 2026
    ACUS02 KWNS 251735
    SWODY2
    SPC AC 251734

    Day 2 Convective Outlook
    NWS Storm Prediction Center Norman OK
    1234 PM CDT Sat Apr 25 2026

    Valid 261200Z - 271200Z

    ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS CENTRAL/EASTERN KANSAS...WEST-CENTRAL MISSOURI...SOUTHEAST NEBRASKA...

    ...SUMMARY...
    Isolated to widely scattered severe storms with potential to produce large/very-large hail severe/damaging winds and a couple of strong
    tornadoes are possible by early Sunday evening across parts of the
    central and southern Great Plains.

    ...Synopsis...
    A shortwave trough will eject into the central Plains late Saturday.
    A surface low develop in western/central Kansas. A dryline will
    drape south and westward into Oklahoma and Texas. A warm front will
    be situated within parts of the mid-Missouri/mid-Mississippi
    Valleys.

    ...Central Plains into mid-Missouri Valley...
    Uncertainty remains in the exact evolution of convection across the
    central Plains and mid-Missouri Valley. While stronger mid-level
    ascent is expected this far north, the timing of the shortwave
    trough will likely be after 00Z. Outflow from convection on Saturday
    will play a role in where severe convection eventually develops. Two
    zones are currently evident in model guidance. One will be along
    potential outflow near the KS/MO border into southeast NE where a
    weak surface low could develop. The triple point and main surface
    low in western/central KS will be the other. Some guidance shows
    warm advection storms spreading northeastward early Sunday which
    would complicate the forecast for the mid-Missouri Valley. There is
    modestly higher confidence in storms developing near the main
    surface low/triple point. Effective shear will be greater than 50
    kt, strong buoyancy of greater than 2500 J/kg MLCAPE, and steep
    mid-level lapse rates will promote a risk for large/very-large hail
    with initial supercells. The tornado risk will likely be maximized
    near the triple point, but how long the greater threat lasts depends
    on speed of upscale growth. With time, one or more clusters/linear
    segments are expected to move eastward and lead to a greater
    severe/damaging wind threat. The southern extent of this potential
    remains uncertain as most guidance has suggested this activity will
    be farther north, more closely tied to the ejecting shortwave
    trough.

    ...Oklahoma...
    The level of severe risk will be highly dependent upon what occurs
    Saturday evening into Sunday morning. Outflow from this activity has
    the potential to limit destabilization across at least portions of central/eastern Oklahoma. This could potentially leave a fairly
    narrow corridor near the dryline where inhibition would be
    minimized. That said, the large-scale ascent will be nebulous at
    best and overcoming the cap will largely be dependent on strong
    heating along the dryline. The nose of the mid-level jet will move
    into the Texas Panhandle/western Oklahoma by late afternoon. Locally
    stronger convergence along the dryline may be enough to initiate an
    isolated storm or two. This scenario remains quite uncertain as
    guidance uniformly does not convect along the dryline. Given greater
    than 50 kt deep-layer shear perpendicular to the dryline, steep
    mid-level lapse rates, and strong low-level shear (especially during
    the evening), storms would be capable of all severe hazards --
    including very-large hail and a strong tornado -- should they
    develop.

    ...Lower Mississippi Valley...
    A remnant MCV from convection on Saturday in OK/northeast Texas will
    likely move southeastward during the day. Moderate mid,
    northwesterly mid-level winds will allow for some continued storm
    organization. The main question will be how much destabilization
    will occur ahead of this feature. Furthermore, weakening 850 mb
    winds will have to overcome by cold pool organization. At least
    isolated wind damage and large hail would be possible.

    ...Northwest Texas into Edwards Plateau/Hill Country...
    Storm initiation along the dryline is not certain given the lack of
    forcing aloft. However, strong heating could promote isolated
    development. Shear would be sufficient for supercells and steep
    lapse rates through the middle troposphere would promote a threat
    for large/very-large hail as well as severe winds.

    ..Wendt.. 04/25/2026

    $$

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