Mesoscale Discussion 1113
   NWS Storm Prediction Center Norman OK
   0724 PM CDT Sun Jul 05 2020

   Areas affected...northeast WY...western SD

   Concerning...Severe Thunderstorm Watch 332...

   Valid 060024Z - 060130Z

   The severe weather threat for Severe Thunderstorm Watch 332
   continues.

   SUMMARY...The propensity for severe gusts will continue to increase
   with a thunderstorm band moving east-northeast from northeast WY
   into southwest SD.  Large hail is possible with discrete supercell
   activity from northeast WY into northwest SD over the next hour.

   DISCUSSION...Radar mosaic as of 0020z shows a congealing band of
   storms over Niobrara, Converse, and Weston counties in WY as this
   activity moves to the east-northeast and approaches the Black Hills
   later this evening.  The 00z Rapid City observed sounding showed
   steep mid-level lapse rates (8.6 degrees C/km in the 700-500mb
   layer) with 40-kt 500mb flow increasing to above 50 kt around 300mb.
   Surface analysis indicates although some convective overturning has
   occurred with earlier storms near the Black Hills, it appears the
   airmass has not been appreciably modified with the rain-cooled air. 
   Therefore it seems likely a moist/unstable boundary layer is in
   place ahead of the band of storms over northeast WY moving into SD
   over the next few hours.  The risk for 60-75 mph gusts will
   continue.  Large hail 1.0-2.5 inches in diameter is also possible
   with discrete supercells over the next hour from northeast WY into
   northwest SD and far southwest ND.

   ..Smith.. 07/06/2020

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

   ATTN...WFO...BIS...UNR...CYS...BYZ...RIW...

   LAT...LON   44180627 46220267 46190191 45740228 44740401 43750288
               42900359 42680449 44180627