Storm Prediction Center Mesoscale Discussion 1990

   Mesoscale Discussion 1990
   NWS Storm Prediction Center Norman OK
   0725 PM CDT Mon Aug 18 2025

   Areas affected...South Dakota

   Concerning...Severe Thunderstorm Watch 600...

   Valid 190025Z - 190230Z

   The severe weather threat for Severe Thunderstorm Watch 600
   continues.

   SUMMARY...Isolated severe thunderstorms will linger this evening.

   DISCUSSION...Weak short-wave trough has topped the ridge and is
   digging southeast across eastern ND/northern SD. This feature
   appears to be aiding isolated thunderstorms across northwestern SD
   early this evening. Latest surface analysis suggests this activity
   trails the main wind shift, but is digging southeast within a steep
   lapse-rate environment characterized by MLCAPE on the order of 2000
   J/kg. Even so, MRMS data suggests hail cores have weakened a bit
   over the last half hour or so. Hail and wind continue to be a
   concern with these isolated robust updrafts.

   ..Darrow.. 08/19/2025

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

   ATTN...WFO...ABR...UNR...

   LAT...LON   43280331 45740332 45779972 43319971 43280331 

   MOST PROBABLE PEAK WIND GUST...65-80 MPH
   MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN