• DAY2 3/5 Risk Area Posted

    From Mike Powell@618:250/10 to All on Wed Jun 10 07:51:26 2026
    ACUS02 KWNS 100547
    SWODY2
    SPC AC 100545

    Day 2 Convective Outlook
    NWS Storm Prediction Center Norman OK
    1245 AM CDT Wed Jun 10 2026

    Valid 111200Z - 121200Z

    ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS
    NORTHEAST MISSOURI...PARTS OF SOUTHERN AND EASTERN IOWA...SOUTHERN WISCONSIN...NORTHERN AND CENTRAL ILLINOIS...NORTHERN INDIANA...PARTS
    OF CENTRAL AND SOUTHERN LOWER MICHIGAN...AND FAR NORTHWEST OHIO...

    ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS SURROUNDING THE
    ENHANCED RISK FROM THE SOUTHERN PLAINS INTO THE UPPER GREAT
    LAKES...AND ACROSS THE MID-ATLANTIC INTO CENTRAL APPALACHIANS...

    ...SUMMARY...
    Scattered to numerous severe storms capable of potentially strong
    tornadoes, large hail greater than two inches in diameter, and
    destructive winds with gusts in excess of 75 mph appear likely from
    portions of the lower Missouri and mid Mississippi Valleys into the
    upper Great Lakes. Widely scattered severe storms capable of
    damaging winds and large hail are possible across the Southern
    Plains, as well as the Mid-Atlantic into central Appalachians.

    ...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 of 60-80+ kt. Elsewhere, northwest flow pattern
    will prevail in the mid levels across the Mid-Atlantic, with a
    series of weaker disturbances moving through that region.

    At the surface, low pressure initially over north-central KS
    Thursday morning will develop into central lower MI by Thursday
    night. The surface low will be developing along a composite
    outflow-warm front that will be rapidly lifting north through the
    Midwest into the upper Great Lakes. Meanwhile, a trailing cold front
    will advance southeast through the lower MO and mid MS Valleys, with
    the southwestward extension of the boundary settling south into the
    southern Plains.

    ...Mid/lower Missouri Valley into the Mid Mississippi Valley and
    upper Great Lakes...

    There is good model agreement that a cluster of severe storms,
    including supercells, will be ongoing at 12z Thursday across the mid
    MO Valley, immediately northeast of the surface low and within a
    zone of strong, low-level warm advection. The early-day storms are
    expected to grow upscale into an organized MCS with embedded
    supercell and bowing structures across IA by mid to late morning
    amidst a rapidly destabilizing air mass, which will be coincident
    with strong low-level and deep-layer shear. As such, the potential
    for tornadoes (some strong) and corridors of destructive winds in
    excess of 75 mph is expected to increase significantly during the
    morning. The intensifying MCS and its related destructive wind and
    tornado threat is expected to move into southern WI and northern IL
    by early to mid afternoon, and eventually into lower MI by late
    afternoon into evening.

    An additional wave of supercells and/or bowing structures is
    expected to develop along the trailing outflow from the lead MCS, as
    well as along the cold front from eastern IA and northern IL into
    the mid MS Valley during the afternoon into evening. Those storms
    will be capable of tornadoes, large to very large hail, and damaging
    winds with significant gusts, which could become widespread should
    storm mode transition to a bowing line.

    ...Eastern Kansas into the Southern Plains...

    Thunderstorm development is anticipated by mid to late afternoon
    along the cold front amidst a moderate to strongly unstable air
    mass. The models indicate the strongest deep-layer shear remaining
    within the post-frontal environment. Nonetheless, there is some
    signal for 30-40 kt of effective bulk shear to cross the eastern KS
    and western MO segment of the front at an oblique angle, which will
    be supportive of supercell storm modes with a risk for large to very
    large hail and severe wind gusts. Deep-layer shear vectors are
    forecast to align largely parallel with the front across the
    southern Plains, which may contribute to downshear storm seeding,
    leading to more messy modes. Nonetheless, the degree of instability
    will favor vigorous up/downdrafts capable of large hail and damaging winds.

    ...Mid-Atlantic into central Appalachians...

    Daytime heating coupled with dewpoints in the 60s to low 70s are
    expected to yield a weakly capped and moderate to strongly unstable
    afternoon air mass. Forcing for ascent associated with the
    disturbances mentioned in the synopsis are expected to foster
    multiple clusters of thunderstorms capable of damaging winds,
    especially if organized cold pools can develop. There is some model
    signal that a corridor of slightly stronger low-level and deep-layer
    shear will materialize across the lower Hudson Valley Thursday
    afternoon, which would support some potential for supercells capable
    of large hail and perhaps a brief tornado.

    ..Mead.. 06/10/2026

    $$
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    * Origin: Capitol City Online (618:250/10)