Mesoscale Discussion 0755
   NWS Storm Prediction Center Norman OK
   0302 PM CDT Wed May 10 2023

   Areas affected...Portions of eastern Wyoming into the Black Hills
   and western Nebraska Panhandle.

   Concerning...Severe potential...Watch possible 

   Valid 102002Z - 102130Z

   Probability of Watch Issuance...60 percent

   SUMMARY...Increasing storm coverage and intensity is expected this
   afternoon and evening.

   DISCUSSION...Storms have developed on the higher terrain across
   south-central Wyoming in a region of upslope flow. Despite only
   modest instability (~500 J/kg MLCAPE per SPC mesoanalysis), this
   should be sufficient for severe storms and potentially supercells
   given the strong forcing beneath strong diffluence aloft and
   effective shear around 35 knots (per SPC mesoanalysis and the CYS
   VWP).
    
   Additional towers are developing off of the Black Hills with the
   potential for one or two storms this afternoon/evening.

   Given the potential for a supercell storm mode, large hail will be a
   threat, and given the large temperature/dewpoint spreads, severe
   wind gusts will also be possible. Unidirectional flow in the lowest
   2-3 km (as seen on the CYS VWP) should limit the tornado potential
   this afternoon.

   Forecast soundings indicate a very slow storm motion (10 to 20
   knots). Therefore, it may take awhile for storms to move off of the
   higher terrain. Given the deep upslope flow in the region and
   approaching mid-level shortwave trough and an uncapped atmosphere
   across eastern Wyoming, cannot rule out isolated storm development,
   but it is possible the majority of storms will remain back along the
   terrain until much later this evening when storms move north into
   the area out of northeast Colorado.

   ..Bentley/Guyer.. 05/10/2023

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

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

   LAT...LON   41010656 41550722 41860817 41950859 42000869 42280875
               42940842 43620779 44380640 45040486 45000405 44790337
               43610313 41980359 41050389 41010656