Mesoscale Discussion 1101
   NWS Storm Prediction Center Norman OK
   0557 PM CDT Sat Jul 04 2020

   Areas affected...southwest South Dakota and the South
   Dakota/Wyoming/Nebraska tri-state area.

   Concerning...Severe potential...Watch unlikely 

   Valid 042257Z - 050100Z

   Probability of Watch Issuance...20 percent

   SUMMARY...Thunderstorms developing from southwest South Dakota into
   eastern Wyoming will pose a risk for severe hail and wind over the
   next 1-2 hours.

   DISCUSSION...Thunderstorms developing along a trough axis across
   southwest SD into far eastern WY have shown signs of strong updrafts
   despite relatively weak deep layer shear (effective bulk wind shear
   at around 20-30 knots) and weak forcing for ascent. These strong
   updrafts are likely being supported by  MLCAPE on the order of
   1000-1500 J/kg and steep mid-level lapse rates of 8-9 C/km on top of
   a deep, well mixed boundary layer. These storms will briefly pose a
   risk for severe hail with the stronger updraft pulses prior to
   becoming outflow dominant or experiencing inhibiting storm
   interactions from neighboring convection along the trough axis.
   Steep low-level lapse rates associated with the well-mixed boundary
   layer coupled with a dry 1-3 km sub-cloud layer will also support
   the potential for severe wind gusts with any thunderstorm outflow.

   ..Moore.. 07/04/2020

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

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

   LAT...LON   42630477 43150408 43540319 43870226 44240171 44130109
               43820102 43220156 42940216 42370383 41880455 41880507
               42240514 42630477