• MESO: Mesoscale Discussion 1978

    From COD Weather Processor@1:2320/105 to wx-storm@lists.illinois.edu on Fri Aug 23 20:14:34 2024
    ACUS11 KWNS 232014
    SWOMCD
    SPC MCD 232013=20
    MTZ000-IDZ000-232215-

    Mesoscale Discussion 1978
    NWS Storm Prediction Center Norman OK
    0313 PM CDT Fri Aug 23 2024

    Areas affected...portions of western and central Montana

    Concerning...Severe potential...Watch possible=20

    Valid 232013Z - 232215Z

    Probability of Watch Issuance...60 percent

    SUMMARY...Thunderstorms will increase in coverage and intensity over
    the next few hours across western and central Montana. Isolated
    damaging gust of 55-70 mph are possible, along with a few instances
    of hail to near one inch diameter.

    DISCUSSION...Gradual destabilization is occurring over the MCD area
    as temperatures have warmed into the 80s F this afternoon.
    Boundary-layer moisture will remain meager, but steep midlevel lapse
    rates/cool temperatures aloft will support MLCAPE increasing to
    around 500-1000 J/kg through early evening. Deepening cumulus is
    noted over the mountains and thunderstorms are expected to increase
    in coverage over the next couple of hours as stronger ascent
    overspreads the region.=20

    Favorable vertical shear will support organized updrafts/clusters,
    while dry low-levels and very steep low-level lapse rates support
    strong/severe gusts. Elongated/straight hodographs in conjunction
    with favorable midlevel instability/shear will also support isolated
    marginally severe hail with more intense/longer-lived updrafts.
    While some MLCIN remains over the region, additional heating and
    increasing ascent should gradually erode inhibition, but overall
    poor vertical moisture profiles will limit instability.
    Nevertheless, a severe thunderstorm watch may become necessary,
    especially if convection across southwest MT/eastern ID sufficiently
    organizes into forward propagating clusters with time as this
    activity shifts north/northeast.

    ..Leitman/Guyer.. 08/23/2024

    ...Please see https://urldefense.com/v3/__http://www.spc.noaa.gov__;!!DZ3fj= g!_amU2SKWrpH-wV5F1AT6AsNzm_5sVOnNe1YdiLdId1N2LhoohJQSnYhnoHn1ZZYOvRlT0wjoR= DQ6sQ6iVRcKStFErD0$ for graphic product...

    ATTN...WFO...BYZ...TFX...MSO...

    LAT...LON 47561510 48721479 48931407 49031285 48991101 48061016
    47261004 46551016 46311028 45981076 45781140 45591292
    45911393 46921475 47561510=20


    =3D =3D =3D
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