• MESO: Mesoscale Discussion 1380

    From COD Weather Processor@1:2320/127 to wx-storm@lists.illinois.edu on Mon Jun 29 17:42:26 2026
    ACUS11 KWNS 291742
    SWOMCD
    SPC MCD 291741=20
    NDZ000-291945-

    Mesoscale Discussion 1380
    NWS Storm Prediction Center Norman OK
    1241 PM CDT Mon Jun 29 2026

    Areas affected...Central North Dakota

    Concerning...Severe potential...Watch likely=20

    Valid 291741Z - 291945Z

    Probability of Watch Issuance...80 percent

    SUMMARY...The potential for severe thunderstorms capable of all
    hazards is expected to increase by 19-20Z. A watch is likely.

    DISCUSSION...Recent trends in visible satellite and radar data
    indicate a gradual increase in shower and thunderstorm development
    across western ND into northwest SD. That activity is located to the
    west of a n-s-oriented stationary front/inverted trough located over
    central ND and within a zone of increased forcing for ascent
    preceding a short-wave trough and associated mid-level jet streak
    pivoting through eastern WY. To the east of the front, dewpoints in
    the 70s and a gradually warming boundary layer are contributing to a
    moderately unstable and increasingly uncapped air mass with MLCAPE
    of 1000-2000+ J/kg, per latest objective analysis.

    The current expectation is for surface-based storm development to
    occur in the vicinity of the front/trough by 19-20Z within a
    kinematic environment featuring low-level easterly winds veering to
    southerly in the mid/upper levels with 50-60 kt of effective bulk
    shear. As such, the potential will exist for initial supercell storm
    modes with an associated risk for large to very large hail and
    perhaps a few tornadoes. There is some signal in recent CAM guidance
    that initial storms could evolve into bowing segments, which would
    be supportive of an increased damaging wind threat.

    ..Mead/Guyer.. 06/29/2026

    ...Please see https://urldefense.com/v3/__http://www.spc.noaa.gov__;!!DZ3fj= g!75Ec_LIZh8Q71_ERlfWcVpnZQrz07hV1kUa1AsyRP67jskKjh8qEO58Lv2PTwTJPfBULHqIjZ= JhRlTpCDYyOfBbLCvE$ for graphic product...

    ATTN...WFO...FGF...BIS...

    LAT...LON 46630121 47940135 48710100 48939969 48699864 47839809
    47199851 46629898 46189942 46090048 46630121=20

    MOST PROBABLE PEAK TORNADO INTENSITY...100-125 MPH
    MOST PROBABLE PEAK WIND GUST...55-70 MPH
    MOST PROBABLE PEAK HAIL SIZE...1.50-2.50 IN


    =3D =3D =3D
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    * Origin: Capitol City Weather Station (1:2320/127)