• DAY3 3/5 RISK AREA POSTED

    From Mike Powell@618:250/6 to All on Wed Apr 15 08:48:08 2026
    ACUS03 KWNS 150729
    SWODY3
    SPC AC 150728

    Day 3 Convective Outlook
    NWS Storm Prediction Center Norman OK
    0228 AM CDT Wed Apr 15 2026

    Valid 171200Z - 181200Z

    ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS
    OF NORTHERN OKLAHOMA AND EASTERN KANSAS...MISSOURI...IOWA...AND FAR
    NORTHWEST ILLINOIS...

    ...SUMMARY...
    Widespread severe thunderstorms are expected from parts of the
    southern Plains to the Middle and Upper Mississippi Valley vicinity
    on Friday and Friday night. All severe hazards will be possible.

    ...Southern Plains to MS Valley...

    A robust upper trough will eject eastward from the northern High
    Plains and central Rockies to the Upper Midwest and central Plains
    on Friday. As this occurs, strong deep-layer southwesterly flow will
    overspread portions of the central/southern Plains to the Mid/Upper
    MS Valley and Great Lakes. Flow at 850-700 mb around 40-60 kt will
    be common. At the surface, a cold front will extend from northern MN
    to a low over eastern NE Friday morning. Meanwhile, a dryline will
    extend southwest from the NE low into central KS, northwest OK and
    western TX. A warm front initially arcing across central IA into
    south-central IL will lift northward through the period ahead of the eastward-advancing surface low tracking across northern IA/southern
    MN into WI. A warm sector characterized by mid/upper 60s F dewpoints
    will be in place across the southern Plains to the Mid-MS Valley by
    midday, with a narrow plume of low 60s F dewpoints extending north
    into portions of eastern MN and WI. Steep midlevel lapse rates (7-8
    C/km) will overspread this moist boundary layer, resulting in
    moderate to strong destabilization.

    As strong ascent overspreads the aforementioned surface boundaries
    by mid afternoon, widespread thunderstorm development is expected.
    While initial supercells are possible given a favorable
    thermodynamic environment and supercell vertical wind profiles,
    linear forcing along the front combined with strong deep-layer
    southwesterly flow parallel to the initiating boundary may result in
    rapid upscale development into a QLCS, particularly from northeast
    KS/northwest MO into IA. A well-organized line of convection will
    pose a damaging wind risk along with possible QLCS tornadoes as
    convection develops eastward through the afternoon/evening. If any
    discrete supercells develop, an all-hazards risk will also accompany
    that activity.

    Further south across southern KS into OK, supercell development may
    be more probable, at least initially. Convection will initially
    develop along the dryline prior to the cold front overtaking this
    boundary later in the evening. Any supercells that develop and can
    maintain discrete characteristics will pose a risk for very large
    hail, strong tornadoes, and damaging winds. With time, the cold
    front will overtake the dryline during the evening and move
    southeast overnight. Linear convection is expected along the front,
    posing a damaging wind and isolated tornado risk during the
    nighttime hours.

    Capping, weakening large-scale ascent and more modest vertical shear
    with southern extent may limit storm potential along the dryline in western/west-central TX.

    ..Leitman.. 04/15/2026

    $$
    --- MultiMail/DOS
    * Origin: Project Scorpio TEST (618:250/6)
  • From Mike Powell@618:250/6 to All on Thu Apr 23 08:35:18 2026
    ACUS03 KWNS 230728
    SWODY3
    SPC AC 230727

    Day 3 Convective Outlook
    NWS Storm Prediction Center Norman OK
    0227 AM CDT Thu Apr 23 2026

    Valid 251200Z - 261200Z

    ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS
    OF SOUTH-CENTRAL KANSAS INTO CENTRAL AND EASTERN OKLAHOMA AND FAR
    NORTHWEST ARKANSAS...

    ...SUMMARY...
    Severe thunderstorms will likely develop across portions of Oklahoma
    and Kansas during the evening. These storms will pose a risk of very
    large hail, damaging winds, and a couple of tornadoes. Isolated
    severe thunderstorms may also develop across portions of North Texas
    during the afternoon.

    ... Synopsis ...

    Increasingly diffluent southwest flow will overspread the Southern
    and Central Plains on Saturday as the midlevel pattern responds to a
    strong shortwave trough/vorticity maximum moving into the Southwest.
    This will induce strong southerly winds across the Plains, helping
    to quickly draw an old frontal boundary northward. This boundary
    should be oriented from northwest to southeast across portions of
    Oklahoma by late Saturday.

    ... Portions of Kansas, Oklahoma, and western Arkansas ...

    Most of the day should be devoid of thunderstorms as mid-level
    heights rise downstream of a digging trough across the Southwest. At
    the same time, strong southerly winds will transport Gulf moisture
    northward from the far Southern Plains into the Central Plains.
    Diurnal heating of this airmass will result in the development of
    strong instability across much of the area, as maximum SBCAPE values
    approach 4000 J/kg across portions of north Texas into central Oklahoma.

    During the late evening a subtle perturbation within the southwest
    flow is forecast to approach Oklahoma. In response to this, the
    low-level jet is forecast to increase to between 30 and 40 knots. As
    it crosses the northward moving warm front, this warm-air
    advection/isentropic ascent will combine with modest large-scale
    ascent from the approaching midlevel perturbation to support
    scattered thunderstorm develop on the north side of the moisture
    gradient. Although differences exist between the various models, the
    generic depiction of forecast soundings show long hodographs with
    varying degrees of low-level curvature in the presence of 2000-3000
    J/kg of MUCAPE. Thus, any storm that develops within the environment
    will be capable of producing all hazards initially. With time,
    thunderstorms should grow upscale into one or more southeast moving
    bowing segments capable of producing damaging winds with perhaps a
    QLCS tornado threat.

    ... North Texas into Southern Oklahoma ...

    Diurnal heating of a moist airmass to the east of a dryline will
    result in an extremely unstable airmass developing by the afternoon.
    Although the region will be devoid of large-scale forcing for
    ascent, temperatures in the 90Fs to the west of the dryline may be
    sufficient to induce dryline circulations capable of initiating
    isolated thunderstorms. Any thunderstorm that develops will be
    capable of producing very large hail.

    ..Marsh.. 04/23/2026

    $$
    --- MultiMail/DOS
    * Origin: Project Scorpio TEST (618:250/6)
  • From Mike Powell@618:250/6 to All on Fri Apr 24 09:08:44 2026
    ACUS03 KWNS 240731
    SWODY3
    SPC AC 240730

    Day 3 Convective Outlook
    NWS Storm Prediction Center Norman OK
    0230 AM CDT Fri Apr 24 2026

    Valid 261200Z - 271200Z

    ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS SUNDAY EVENING
    INTO SUNDAY NIGHT ACROSS MUCH OF KANSAS AND ADJACENT PORTIONS OF
    NORTHERN OKLAHOMA...WESTERN MISSOURI...

    ...SUMMARY...
    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...
    A remnant elongated cyclonic mid-level circulation/shear axis may
    tend to shift north-northeastward through Saskatchewan/Manitoba
    through this period, while larger-scale troughing along an axis
    inland of the U.S. Pacific coast through the Hudson Bay vicinity
    weakens through this period. However, mid/upper ridging across southern/central Mexico into portions of the southern Great Plains
    and lower Mississippi Valley appears likely to maintain considerable
    strength, while a notable short wave perturbation accelerates out of
    the southern Great Basin/lower Colorado Valley, within strong
    southwesterly flow between the two features.

    Models suggest that stronger mid-level height falls will generally
    overspread the eastern Colorado/western Kansas/southwest Nebraska
    vicinity of the high plains late Sunday afternoon into evening,
    before reaching southern portions of the middle Missouri Valley by
    12Z Monday, accompanied by a developing low within the northern
    portion of deepening surface troughing extending southward into the
    southern Great Plains. Another low, developing by Sunday afternoon
    across the southeastern Colorado/Texas and Oklahoma Panhandle region
    may reach portions of central Kansas.

    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 a warm frontal zone may become better defined by early
    Sunday evening across southern Kansas into the Ozark Plateau
    vicinity, before tending to shift northward.

    ...Great Plains...

    Although though there is not a strong signal yet evident within
    latest model output concerning potential convective evolution during
    this period, at least isolated to perhaps widely scattered supercell development may initiate along the dryline as far south as northwest
    Texas by late Sunday afternoon, in the presence of destabilization
    and strengthening shear. By early Sunday evening, this probably
    will include enlarging, clockwise curved low-level hodographs
    beneath a strengthening southerly low-level jet. This may become
    supportive of increasing potential for a couple of strong tornadoes,
    in addition to large hail, with increasing storm coverage probable
    across the western Kansas vicinity.

    Gradually, large-scale forcing for ascent, focusing along the warm
    front, may support one or two upscale growing clusters of storms
    spreading into the middle/lower Missouri Valley overnight, with
    damaging wind gusts becoming the more prominent severe hazard along
    with perhaps some continuing risk for tornadoes.

    ..Kerr.. 04/24/2026

    $$
    --- MultiMail/DOS
    * Origin: Project Scorpio TEST (618:250/6)
  • From Mike Powell@618:250/10 to All on Fri May 15 09:24:43 2026
    ACUS03 KWNS 150732
    SWODY3
    SPC AC 150731

    Day 3 Convective Outlook
    NWS Storm Prediction Center Norman OK
    0231 AM CDT Fri May 15 2026

    Valid 171200Z - 181200Z

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

    ...SUMMARY...
    Severe storms will be likely Sunday from portions of the central and
    southern High Plains into the Upper Midwest. Supercells capable of
    all hazards will be possible before upscale growth and an emerging
    damaging wind risk continues into the evening.

    ...Synopsis...
    An upper-level trough will begin to eject across the Intermountain
    West on D3/Sunday with a more subtle shortwave trough moving across
    the central Plains. As a result, deepening low pressure will develop
    across eastern Colorado/western Kansas with strengthening southerly
    flow and warm moist advection south of a warm front lifting
    northward into the northern Plains and upper Midwest. Early in the
    period, elevated storms will likely be ongoing across portions of
    Iowa into southern Minnesota. Scattered severe storms capable of all
    hazards will be expected to develop near the warm front/low across
    eastern Colorado into Nebraska and across southern South Dakota
    continuing into portions of the upper-Midwest along the cold front
    through the evening. A more isolated and conditional threat for
    severe storms will extend southward along the dryline from western
    Kansas into western Oklahoma.

    ...Central Plains into the Upper Midwest...

    Early day elevated convection is expected to move across portions of
    Iowa into the upper-Midwest. This will pose some risk for severe
    hail through the morning. Across the central Plains, strong daytime
    heating is expected to yield moderate to strong instability across
    much of the central Plains. This in combination with strong deep
    layer shear suggests a rather volatile environment, particularly
    across central Nebraska into southern South Dakota/northwestern
    Iowa. Guidance suggests that thunderstorms will develop across
    eastern Colorado into Nebraska by the afternoon. Initial
    thunderstorm development will likely be supercellular and capable of
    all hazards including large to very large hail, damaging wind, and
    tornadoes. As the front sags southward through the evening, eventual
    upscale growth into a squall line is expected by the evening. A
    strong 50 kt low-level jet will ramp up into the evening, which may
    support a continuing potential for tornadoes, some of which may be strong.

    ...Western Kansas into western Oklahoma...

    A more conditional threat may extend southward along the dryline
    into western Kansas and western Oklahoma. Guidance suggests some
    signal for isolated supercells to develop along and east of the
    dryline Sunday afternoon. The environment here will conditionally
    favor large to very large hail, damaging wind, and perhaps a tornado
    or two with the strengthening low-level jet in the evening.

    ..Thornton.. 05/15/2026

    $$
    --- SBBSecho 3.28-Linux
    * Origin: Capitol City Online (618:250/10)
  • From Mike Powell@618:250/10 to All on Sat May 16 08:45:27 2026
    ACUS03 KWNS 160737
    SWODY3
    SPC AC 160736

    Day 3 Convective Outlook
    NWS Storm Prediction Center Norman OK
    0236 AM CDT Sat May 16 2026

    Valid 181200Z - 191200Z

    ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS PORTIONS OF THE SOUTHERN/CENTRAL PLAINS INTO THE MIDWEST...

    ...SUMMARY...
    Numerous strong thunderstorms are expected to develop Monday along a
    cold front and dryline extending from the Great Lakes into the
    central/southern Plains. Supercells capable of all hazards
    (including very large hail and strong to intense tornadoes) will be
    possible across central Kansas into southeastern Nebraska.

    ...Synopsis...
    On Monday, the western trough will take on a negative tilt before
    ejecting across the central Plains, with strong southwesterly flow
    aloft overspreading the region. As a result, a strong surface low
    will development across western Kansas. A surface cold front will
    extend northward to a secondary surface low across the upper
    Midwest. A dryline will extend southward across portions of western
    Kansas into western Oklahoma. Numerous thunderstorms are expected to
    develop along and ahead of the cold front and further south along
    the dryline Monday afternoon and evening from Nebraska into central Kansas.

    ...Central Kansas into southeastern Nebraska...

    A volatile environment is expected to be in place ahead of the
    dryline across central Kansas Monday afternoon, with moderate to
    strong instability, strong deep layer shear, and steep low to
    mid-level lapse rates. This will favor supercells as the primary
    mode with developing thunderstorms along the dryline in the
    afternoon, with potential for large to very large hail (some 2-4
    inch). Through the afternoon and evening, a 40-50 kt southerly low
    level jet will shift into central Kansas with large clockwise
    enhancement of low-level hodographs. Should the mode be able to
    remain discrete supercells, strong to intense tornadoes will be
    possible across central Kansas into southeastern Nebraska. This in
    combination with potential for very large hail may warrant higher
    probabilities as mesoscale details become clearer.

    As the front shifts southward through time, upscale growth will be
    favored with increasing probabilities for damaging winds.

    ...Iowa into Wisconsin and the Great Lakes Region...

    Widely scattered thunderstorm development is expected further north
    along the front into Iowa/Wisconsin and north into the Great Lakes
    Region. Early day convection may be ongoing at the start of the
    period within these regions, which may limit how much
    destabilization can occur before the afternoon. Nonetheless,
    guidance suggests potential for damaging wind and perhaps a few
    instances of severe hail with storms along the front Monday
    afternoon and evening.

    ...Western Oklahoma into northern Texas...

    Forcing for ascent will be weaker across the dryline into western
    Oklahoma and northern Texas. Guidance does suggest that a few
    isolated supercells could develop near the dryline, with potential
    for large to very large hail, damaging winds, and perhaps a tornado.
    Given the strong flow aloft and better large scale ascent will
    reside further north in Kansas, mode may quickly become messy with
    uncertainty in overall coverage at this time.

    ..Thornton.. 05/16/2026

    $$
    --- SBBSecho 3.28-Linux
    * Origin: Capitol City Online (618:250/10)
  • From Mike Powell@618:250/10 to All on Sun Jun 7 09:10:22 2026
    ACUS03 KWNS 070723
    SWODY3
    SPC AC 070722

    Day 3 Convective Outlook
    NWS Storm Prediction Center Norman OK
    0222 AM CDT Sun Jun 07 2026

    Valid 091200Z - 101200Z

    ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS OVER CENTRAL
    NORTH DAKOTA AND NORTH-CENTRAL SOUTH DAKOTA...

    ...SUMMARY...
    Scattered to numerous severe thunderstorms are expected to develop
    across portions of the northern Plains into Upper Mississippi Valley
    Tuesday afternoon into night. All severe-weather hazards are
    possible. Isolated to widely scattered severe storms may also occur
    across the central Plains, with a risk for large hail and damaging winds.

    ...Synopsis...

    A short-wave trough and attending mid/upper-level jet streaks over
    the northern Rockies Tuesday morning will overspread the northern
    Plains by afternoon. Farther upstream, a significant short-wave
    trough will assume an increasing negative tilt while translating
    into the northern High Plains early Tuesday morning. At the surface,
    a cyclone linked with the lead short-wave trough will deepen while
    developing from southeast MT into western ND by afternoon.
    Meanwhile, an associated Pacific front will push east into the
    western Dakotas, with more of a dryline structure evident from
    southwest NE into the OK and TX Panhandles.

    ...Northern and Central Plains into Upper Mississippi Valley...

    An active severe-weather period is anticipated Tuesday afternoon
    into night, especially across the northern Plains, where all
    severe-weather hazards are possible.

    While the pre-frontal air mass over the western Dakotas is not
    expected to be overly moist with dewpoints in the 50s to low 60s,
    strong daytime heating and steep mid-level lapse rates will
    contribute to moderate to strong instability by mid to late
    afternoon. Some potential for early-day storms will exist in
    northern ND, within a zone of persistent warm advection. Additional,
    more intense thunderstorm activity is expected by mid afternoon from
    the southern fringe of the early-day convection south along the
    front as forcing for ascent increases with the approach of the
    short-wave trough.

    Vertically veering wind profiles with 40-50+ kt of deep-layer shear
    will favor supercells capable of large to very large hail initially.
    Some tornado threat could materialize during the evening hours as
    LCL heights lower and the low-level shear increases. With time,
    storms may grow upscale into clusters, with an increasing risk for
    damaging winds spreading east through the Red River Valley.

    Farther south, a number of models develop isolated to widely
    scattered storms during the afternoon along the dryline in western
    KS amidst a marginally sheared, but moderate to strongly unstable
    environment. There is some signal that an MCS could evolve from that
    activity across the mid to lower MO Valley Tuesday evening. Only 5% total-severe probabilities will be added in those areas, due to
    uncertainty in that scenario.

    ..Mead.. 06/07/2026

    $$
    --- SBBSecho 3.28-Linux
    * Origin: Capitol City Online (618:250/10)
  • From Mike Powell@618:250/10 to All on Mon Jun 8 09:58:55 2026
    ACUS03 KWNS 080723
    SWODY3
    SPC AC 080722

    Day 3 Convective Outlook
    NWS Storm Prediction Center Norman OK
    0222 AM CDT Mon Jun 08 2026

    Valid 101200Z - 111200Z

    ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS
    OF EASTERN MINNESOTA...MUCH OF WISCONSIN...CENTRAL AND EASTERN
    IOWA...AND NORTHWEST ILLINOIS...

    ...SUMMARY...
    Scattered to numerous severe thunderstorms capable of large to very
    large hail, tornadoes, and damaging winds with significant gusts
    appear likely across portions of the upper Mississippi Valley and
    Midwest Wednesday afternoon into night. More sporadic occurrences of
    large hail and damaging winds are possible into the central Plains.

    ...Synopsis...

    The 00z models have trended toward a similarly timed, but slightly
    more amplified short-wave trough, which will move through the
    northern Plains into upper MS Valley, in tandem with a 50-60+ kt jet
    streak. Meanwhile, a stronger upstream system is forecast to amplify
    across the northern and central Plains late Wednesday night into
    Thursday morning.

    At the surface, a cold front initially from the eastern Dakotas into
    central High Plains will push east into the upper Great Lakes. A
    frontal wave is forecast to develop from eastern SD into central MN
    by afternoon, where it may link with an outflow boundary extending
    into central WI. The trailing extension of the front is expected to
    stall across the mid or lower MO Valley in response to the deepening
    of a surface low over the central or southern High Plains.

    ...Upper Mississippi Valley into upper Great Lakes and mid/lower
    Missouri Valley...

    A very moist boundary layer, characterized by boundary-layer
    dewpoints in the upper 60s to mid 70s is forecast ahead of the
    front, which coupled with steep lapse rates, will contribute to
    moderate to strong instability by afternoon. Thunderstorms are
    expected to develop by early afternoon along the surface front and
    any outflow boundaries across the upper MS Valley, with subsequent, south/southwestward storm development into IA and the lower MO
    Valley by mid to late afternoon. The strongest deep-layer shear is
    forecast across the upper MS Valley into upper Midwest, with
    decreasing bulk-shear magnitudes with southward extent being offset
    by stronger instability. The CAPE/shear parameter space will favor
    organized storm modes including supercells and bowing structures.
    Large to very large hail will likely be the initial hazard, with the
    threat for damaging winds and tornadoes increasing as storms move
    into WI, eastern IA, and northwest IL, where stronger low-level
    shear is forecast.

    Additional, isolated to widely scattered storms are anticipated by
    late afternoon into evening across portions of the lower MO Valley
    into at least eastern KS. While vertical shear will be somewhat
    marginal, the strong instability will support strong up/downdrafts
    capable of isolated occurrences of large hail and damaging winds.

    A separate, elevated thunderstorm regime may materialize Wednesday
    night into Thursday morning across portions central/eastern NE and
    northern KS as low-level warm advection increases ahead of the next
    mid-level trough moving into the northern and central Plains. The
    strongest storms will be capable of a large-hail threat.

    ..Mead.. 06/08/2026

    $$
    --- SBBSecho 3.28-Linux
    * Origin: Capitol City Online (618:250/10)
  • From Mike Powell@618:250/10 to All on Tue Jun 9 08:11:24 2026
    ACUS03 KWNS 090727
    SWODY3
    SPC AC 090726

    Day 3 Convective Outlook
    NWS Storm Prediction Center Norman OK
    0226 AM CDT Tue Jun 09 2026

    Valid 111200Z - 121200Z

    ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM NORTHEAST
    MISSOURI THROUGH EASTERN IOWA...NORTHERN AND CENTRAL ILLINOIS AND
    SOUTHERN WISCONSIN INTO WESTERN LOWER MICHIGAN...

    ...SUMMARY...
    Scattered to numerous severe storms capable of potentially strong
    tornadoes, large hail, and destructive winds appear likely from
    portions of the lower Missouri and mid Mississippi Valleys into the
    upper Great Lakes. More sporadic occurrences of damaging wind and
    large hail are possible across the southern Plains, upper Ohio
    Valley and lower Great Lakes toward the Mid-Atlantic Coast.

    ...Synopsis...

    A potent short-wave trough initially over the central High Plains
    Thursday morning is forecast to accelerate through the upper Great
    Lakes with a trailing perturbation moving through the central Plains
    into mid MS Valley Thursday night. Both disturbances will be located
    on the cyclonic aside of an unseasonably strong mid-level jet with
    500-mb wind speeds approaching 70-80 kt. The 00z models have slowed
    the progression of the mid-level wave, as well as the associated
    surface low, which is forecast to develop from northeast KS along
    the synoptic front or remnant outflow from overnight storms into
    southern WI by afternoon and northern lower MI or the UP by Thursday night.

    ...Lower Missouri Valley/Mid Mississippi Valley into the Upper Great Lakes...

    A very moist boundary layer will combine with steep mid-level lapse
    rates to yield a moderate to strongly unstable air mass by afternoon
    to the south of the composite surface boundary. A cluster of mainly
    elevated thunderstorms is expected to be ongoing Thursday morning
    across portions of the mid MO Valley, to the northeast of the
    surface low. Those storms are expected to become progressively more surface-based and intense by mid to late morning into afternoon
    while rapidly moving northeast, coincident with the surface low.
    Forecast sounding within the inflow environment of those storms
    indicate strong low-level and deep-layer shear, supportive of
    supercells and bowing segments capable of potentially strong
    tornadoes, in addition to large hail and damaging winds.

    Additional severe storms are expected to develop along the trailing
    front from the lower MO and mid MS Valleys southwest through the
    Ozarks into southern Plains. The progressive nature of the mid-level
    system suggests the potential for long-tracked supercells and bowing
    structures capable of tornadoes and swaths of destructive winds.

    ...Upper Ohio Valley and Lower Great Lakes to the Mid-Atlantic Coast...

    While large-scale forcing for ascent is expected to remain
    relatively weak, model guidance indicates scattered, afternoon storm development from the lee of the lower Great Lakes through the
    central Appalachians to the vicinity of a lee trough in the
    Mid-Atlantic. Vertical shear is expected to remain relatively weak;
    however, the presence of a moist and moderately unstable air mass
    will support wet microburst activity and an associated risk for
    sporadic damaging winds.

    ..Mead.. 06/09/2026

    $$
    --- SBBSecho 3.28-Linux
    * Origin: Capitol City Online (618:250/10)
  • From Mike Powell@618:250/10 to All on Mon Jun 15 07:30:06 2026
    ACUS03 KWNS 150728
    SWODY3
    SPC AC 150727

    Day 3 Convective Outlook
    NWS Storm Prediction Center Norman OK
    0227 AM CDT Mon Jun 15 2026

    Valid 171200Z - 181200Z

    ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS
    OF THE MID-MISSISSIPPI VALLEY INTO INDIANA...

    ...SUMMARY...
    An all-hazards severe thunderstorm episode is expected across
    portions of the Middle Mississippi Valley into Indiana on Wednesday.
    Intense thunderstorms may produce swaths of damaging wind, as well
    as strong tornadoes and large hail.

    ...Midwest...

    A midlevel shortwave trough is forecast to move from the northern
    Plains through the Upper Midwest and Great Lakes region on
    Wednesday. As this occurs, very strong deep-layer flow, especially
    for this time of year, will move across portions of the Mid-MS
    Valley into the Ohio Valley. A westerly 500 mb jet streak
    characterized by at least 70-80 kt will overspread parts of
    IA/MO/IL/IN in the afternoon and evening. Meanwhile, a 50+ kt
    southwesterly 850 mb low-level jet will spread across the same area
    during the afternoon/evening, just ahead of an
    east/southeast-advancing surface cold front. These strong wind
    fields, in conjunction with a surface low moving eastward across MN
    and the Upper Great Lakes, will aid in northward transport of rich
    boundary layer moisture (upper 60s to near 70 F surface dewpoints).
    Cooling aloft will steepen midlevel lapse rates, and moderate to
    strong destabilization is expected across the warm sector. Overall,
    this pattern should support numerous severe storms. While convective
    evolution remains uncertain, it is likely that at least some initial
    supercell risk will unfold during the afternoon and early evening
    (particularly across MO/IL), with potential for one or more bowing
    MCSs developing with time. This environment will support a risk for
    all severe hazards, and particularly swaths of damaging winds, and
    strong tornadoes.

    Some uncertainty remains regarding the northward extent of the
    severe risk. Most medium range guidance indicates a lead shortwave
    impulse may move across IA/IL early in the day. Coupled with strong
    warm advection across the region, morning thunderstorm develop
    near/north of a warm front oriented from southeast MN into northeast
    IL at midday could suppress northward development of the warm front.
    Likewise, the southwest extent of the risk area into portions of
    KS/OK may be limited by capping concerns, and weaker forcing for
    ascent. Meanwhile, the southward extent of the severe risk across
    the Ohio Valley will be modulated by the stronger westerly component
    of mid/upper flow overnight and slow southward movement of the
    surface cold front. The risk area may shift some in coming days as
    surface boundaries and other mesoscale details become better
    resolved.

    ..Leitman.. 06/15/2026

    $$
    --- SBBSecho 3.28-Linux
    * Origin: Capitol City Online (618:250/10)