• DAY2 3/5 RISK AREA Update

    From Mike Powell@618:250/10 to All on Fri Jun 12 13:09:02 2026
    ACUS02 KWNS 121730
    SWODY2
    SPC AC 121728

    Day 2 Convective Outlook
    NWS Storm Prediction Center Norman OK
    1228 PM CDT Fri Jun 12 2026

    Valid 131200Z - 141200Z

    ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS SATURDAY
    AFTERNOON INTO SATURDAY NIGHT ACROSS EASTERN KANSAS...ADJACENT
    PORTIONS OF SOUTHEASTERN NEBRASKA AND NORTHEASTERN OKLAHOMA...AND
    MUCH OF WESTERN THROUGH CENTRAL MISSOURI...

    ...SUMMARY...
    One or two evolving thunderstorm clusters appear possible across
    parts of the central Great Plains and lower Missouri Valley vicinity
    Saturday afternoon through Saturday night. Some of this activity
    will pose a risk for producing large hail and swaths of strong,
    potentially damaging wind gusts.

    ...Discussion...
    Downstream of amplified mid-level ridging, offshore of the U.S.
    Pacific coast through British Columbia, it appears that flow will
    begin to veer to an increasing northwesterly component across and
    east of the Rockies through this period. Within this regime,
    substantive mid-level troughing is forecast to dig across the Upper
    Midwest, to the southwest of a lingering mid-level low centered
    across northwestern Ontario. Spread within model output remains
    larger concerning short wave perturbations digging through initially
    weaker flow across the Missouri through lower Ohio Valleys, and the
    extent to which they may begin to suppress the northern periphery of subtropical ridging centered over the northern Gulf Basin.

    In lower levels, an initial, convective outflow enhanced, surface
    front overspreading much of the Mid Atlantic through Mid South
    vicinity will likely already be in the process of weakening at the
    outset of the period. However, surges of cooler/drier air will
    continue to develop southward into and through the interior of the
    U.S., with the general leading edge reaching the lower Great Lakes
    through Ohio Valley, Ozarks Plateau and Texas South Plains by 12Z
    Sunday. This may be preceded across the Ohio Valley through western
    slopes of the Appalachians by outflow from extensive prior
    convective development.

    ...Central Great Plains into Missouri Valley...

    The potential for increasing thunderstorm development at the outset
    of the period across eastern Nebraska into western Iowa (near the
    nose of an east-northeastward advecting plume of elevated
    mixed-layer air) coupled with potential for substantive, but
    weakening, remnant convection from overnight overspreading the Ozark
    Plateau, contribute to continuing uncertainty concerning subsequent
    convective development Saturday through Saturday night.
    The evolution of convective outflows, and their impact on
    boundary-layer destabilization, coupled with uncertain short wave
    developments, will substantially impact the timing, location and
    potential upscale growth of potentially stronger thunderstorm development.

    However, beneath the plume of elevated mixed-layer air, a corridor
    of stronger boundary-layer heating and deeper mixing across Kansas
    during the day seems to provide the highest certainty for moderate
    to strong destabilization. Near the nose of this regime, somewhere
    across eastern Kansas into western Missouri, based on a consensus of
    model output, low-level warm advection in the presence of weaker
    inhibition may provide the focus for intensifying thunderstorm
    development by late afternoon. And there appears a general signal
    in the model output that a modifying outflow boundary/zone of
    differential heating may provide a focus for the southeastward
    development of upscale growing convection toward the Mid South
    through Saturday night. As this occurs, increasing thunderstorm
    development also appears probable ahead of the southward advancing
    cold front across Kansas through Oklahoma and the Texas Panhandle vicinity.

    Although deep-layer shear may be initially modest, it may still be
    sufficient to support the evolution of a few supercells capable of
    producing large hail and potential for a couple tornadoes, before
    evolving swaths of strong to severe wind gusts become the more
    prominent threat with organizing clusters into late Saturday
    evening.

    ..Kerr.. 06/12/2026

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