Mesoscale Discussion 1425
   NWS Storm Prediction Center Norman OK
   0231 PM CDT Sat Aug 08 2020

   Areas affected...eastern Wyoming...southwest South Dakota...and the
   Nebraska Panhandle

   Concerning...Severe potential...Watch possible 

   Valid 081931Z - 082130Z

   Probability of Watch Issuance...60 percent

   SUMMARY...Thunderstorms are expected to develop across southeast
   Wyoming over the next couple of hours before moving east with time.
   A wind and hail threat may develop and the area will be monitored
   for a possible severe thunderstorm watch.

   DISCUSSION...Thunderstorms are expected to develop in the next
   couple of hours across southeast Wyoming and southwest South Dakota
   associated with favorable terrain-driven diurnal circulations,
   augmented by mid-level ascent associated with an approaching trough.
   Although the environment here will become increasingly unstable from
   east-to-west as low-level moisture is advected in from the
   east-northeast, a deep, well-mixed boundary layer will limit how far
   west favorable instability profiles will exist.

   The result will be most-unstable CAPE values increasing from 250
   J/kg near the higher terrain of eastern Wyoming to near 5000 J/kg
   across the Nebraska Panhandle. Effective deep-layer shear between
   40-50 knots will support thunderstorm organization/longevity for
   robust updraft pulses. As thunderstorms attempt to move east off the
   terrain toward the Nebraska Panhandle, the threat for hail and wind
   will increase given the better thermodynamic environment. The main
   concern/limiting factor will be the number of storms that are able
   to persist into this better environment.

   The area will continue to be monitored for a potential severe
   thunderstorm watch this afternoon.

   ..Marsh/Grams.. 08/08/2020

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

   ATTN...WFO...LBF...UNR...CYS...RIW...

   LAT...LON   41520207 41250569 44190601 44300262 41520207