• MESO: Mesoscale Discussion 0307

    From COD Weather Processor@1:2320/105 to wx-storm@lists.illinois.edu on Tue Mar 26 18:08:56 2024
    ACUS11 KWNS 261808
    SWOMCD
    SPC MCD 261808=20
    MIZ000-OHZ000-INZ000-262045-

    Mesoscale Discussion 0307
    NWS Storm Prediction Center Norman OK
    0108 PM CDT Tue Mar 26 2024

    Areas affected...much of lower Michigan...northeastern
    Indiana...northwestern Ohio

    Concerning...Severe potential...Watch unlikely=20

    Valid 261808Z - 262045Z

    Probability of Watch Issuance...20 percent

    SUMMARY...An increasingly organized band of showers, and developing thunderstorms, may be accompanied by increasing potential for strong
    to locally severe surface gusts by 4-5 PM EDT. It is still not
    clear that a severe weather watch is needed, but trends are being
    monitored for this possibility.

    DISCUSSION...Weak destabilization within a narrow pre-frontal
    corridor of low-level warming and moistening, coupled with
    large-scale ascent aided by warm advection, has contributed to
    increasing showers across western lower Michigan southward toward
    the Indianapolis IN vicinity. Some lightning has recently been
    noted southeast of South Bend, but low-level lapse rates are still
    relatively modest and the moistening is only contributing to very
    weak CAPE.

    This may be slow to improve, but breaks in cloud cover may allow for
    at least some continuing insolation during the next few hours.=20
    Perhaps more notably, within the left exit region of an intensifying
    mid-level jet (in excess of 100 kt around 500 mb) nosing
    north-northeastward through the lower Ohio Valley, strengthening
    low-level frontogenetic forcing is forecast along the eastward
    advancing front across central lower Michigan through the
    Indiana/Ohio border area by 20-21Z. This may support a
    consolidating and deepening band of convection with increasing
    potential to produce lightning.=20=20

    In the presence of fairly strong (and strongly sheared)
    south-southwesterly lower/mid-tropospheric flow (including 40-50+ kt
    mean ambient flow in the lowest 3-6 km AGL), activity may become
    increasingly organized. Downward mixing of momentum may contribute
    to potentially damaging wind gusts reaching the surface in
    northeastward surging segments, while the line advances eastward
    toward the lower Great Lakes region through late afternoon.

    ..Kerr/Hart.. 03/26/2024

    ...Please see https://urldefense.com/v3/__http://www.spc.noaa.gov__;!!DZ3fj= g!8BEQNIT5tT_M7xaUGqWSk6VW4WNb7v1GZ148C4q0N2k6BPR8dGP3e0lSrpsdiWBcFHKPr3Uxq= uoNtPVU8gUhlGlp2BA$ for graphic product...

    ATTN...WFO...CLE...ILN...DTX...APX...IWX...GRR...

    LAT...LON 40428544 42978529 44938539 44928356 43948281 41398341
    40408392 40428544=20


    =3D =3D =3D
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