• MESO: Mesoscale Discussion 1873

    From COD Weather Processor @1:2320/107 to All on Sunday, August 09, 2026 03:48:22
    ACUS11 KWNS 090348
    SWOMCD
    SPC MCD 090347
    MNZ000-SDZ000-NDZ000-090545-

    Mesoscale Discussion 1873
    NWS Storm Prediction Center Norman OK
    1047 PM CDT Sat Aug 08 2026

    Areas affected...Southern North Dakota into northeast South Dakota
    and far western Minnesota

    Concerning...Severe potential...Watch possible

    Valid 090347Z - 090545Z

    Probability of Watch Issuance...40 percent

    SUMMARY...Elevated thunderstorms developing along the North
    Dakota/South Dakota border may continue to intensify and grow
    upscale over the coming hours. If upscale growth can occur, a more
    pronounced severe risk may emerge and require watch issuance.
    Convective trends are being monitored.

    DISCUSSION...Deep convection has begun to emerge along the ND/SD
    border over the past 30-45 minutes with additional towering, but
    weaker, convection noted in GOES IR imagery over southern and
    eastern ND. Similar to previous attempts at sustained deep
    convection, this activity appears to largely be driven by increasing
    isentropic ascent within the warm advection branch of a weak cyclone
    over the western Dakotas - augmented by a slight uptick in the
    nocturnal jet strength over the past hour (per regional VWPs). This
    emerging convection resides on the northern periphery of a buoyancy
    reservoir with MUCAPE values as high as 4000 J/kg analyzed
    downstream into SD. Additionally, 50-60 knot effective bulk shear
    was recently sampled by the 00 UTC BIS and ABR RAOBs, suggesting
    that intensification/organization of this convection is likely.

    Given the trends in IR imagery, adequate forcing for ascent, and
    downstream environment, it appears possible that some severe threat
    will emerge over the next few hours along the ND/SD border. Latest
    runs of the RRFS appear to be capturing convective trends well and
    suggest additional convection will manifest over the next 1-2 hours
    before growing upscale. If/when this occurs, the potential for
    severe hail and severe wind gusts will likely increase. Convective
    trends are being monitored, and watch issuance may be required if
    convective coverage increases.

    ..Moore/Mosier.. 08/09/2026

    ...Please see https://urldefense.com/v3/__http://www.spc.noaa.gov__;!!DZ3fjg!4Y22NOM95jZ35GnSncppdeI7A-m6prehEWebsqv0hTd9TSMBX-7FJ3mheSXDymufg6rBY41qbWQAk5nCWkiLpiQ_ngw$ for graphic product...

    ATTN...WFO...MPX...FGF...FSD...ABR...BIS...

    LAT...LON 44089833 45710129 46190136 46520111 46710048 46269615
    45709598 45139615 44619650 44369697 44169761 44089833

    MOST PROBABLE PEAK WIND GUST...55-70 MPH
    MOST PROBABLE PEAK HAIL SIZE...1.50-2.50 IN


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    --- scorpsmtpd
    * Origin: capitolcityonline.net * KY, USA (1:2320/107)