Mesoscale Discussion 1325
   NWS Storm Prediction Center Norman OK
   0554 PM CDT Thu Jul 23 2020

   Areas affected...Northeast Montana...Western North
   Dakota...Northwest South Dakota

   Concerning...Severe Thunderstorm Watch 397...

   Valid 232254Z - 240100Z

   The severe weather threat for Severe Thunderstorm Watch 397
   continues.

   SUMMARY...A severe threat will continue across WW 397 for several
   more hours. Isolated large hail and wind damage will be the primary
   threats.

   DISCUSSION...The latest mosaic radar imagery shows strong to severe
   thunderstorms from northwest South Dakota into far southwest North
   Dakota and far eastern Montana. The storms are located along the
   western edge of a strongly unstable airmass where the RAP is
   estimating MLCAPE in the 2000 to 4000 J/kg range. The storms are
   also located just ahead of a shortwave trough that is moving through
   the northern High Plains, evident on water vapor imagery. The
   instability and strong large-scale ascent will support continue
   thunderstorm development in the northern High Plains this evening.
   The latest WSR-88D VWPs at Bismarck and Glasgow show 35 to 40 kt of
   0-6 km shear. In addition, forecast soundings in western North
   Dakota have 700-500 mb lapse rates near 8.0 C/Km. This will be
   favorable for supercells with isolated large hail. Wind damage will
   also be possible with supercells and short multicell line segments.
   The severe threat is expected to persist through the early to mid
   evening as cells gradually move northward across the central and
   northern part of WW 397.

   ..Broyles.. 07/23/2020

   ...Please see www.spc.noaa.gov for graphic product...

   ATTN...WFO...BIS...UNR...BYZ...GGW...

   LAT...LON   48570525 48240523 47290465 45810361 45340301 45210255
               45570217 46920224 47640245 48240317 48680379 48840449
               48750499 48570525