Storm Prediction Center Mesoscale Discussion 1967

   Mesoscale Discussion 1967
   NWS Storm Prediction Center Norman OK
   0255 PM CDT Wed Aug 21 2024

   Areas affected...eastern WY into western SD/NE

   Concerning...Severe potential...Watch possible 

   Valid 211955Z - 212100Z

   Probability of Watch Issuance...40 percent

   SUMMARY...Isolated strong to severe thunderstorms may produce gusts
   of 55-70 mph and hail to 1.5 inches into this evening. Portions of
   the area may need a severe thunderstorm watch, but timing is
   uncertain.

   DISCUSSION...Convection is increasing across WY and western SD/NE
   this afternoon where strong heating into the 90s F has occurred.
   Boundary-layer moisture remains modest across much of the area,
   though 60s F dewpoints are noted into parts of SD. Cool temperatures
   aloft, aiding in steep midlevel lapse rates, are supporting weak to
   moderate instability across the region. High-based storms initially
   developing near higher terrain may pose a risk for strong outflow
   winds. Clustering may occur with eastward extent toward late
   afternoon/early evening as storms move into a more moist and
   unstable environment. Damaging gusts will be possible with this
   activity. Additionally, modest vertical shear amid a steep lapse
   rates environment could support a few instance of large hail in the
   1-1.5 inch range with any stronger/longer-lived thunderstorm cores.
   The MCD area is being monitored for possible watch issuance this
   afternoon.

   ..Leitman/Hart.. 08/21/2024

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

   ATTN...WFO...ABR...LBF...UNR...CYS...

   LAT...LON   41060348 41020469 41070553 41350576 41830586 43370504
               44390444 45020396 45150363 45170238 45000169 44230117
               43100105 41550215 41040322 41060348