Mesoscale Discussion 0799
   NWS Storm Prediction Center Norman OK
   0356 PM CDT Wed Jun 03 2020

   Areas affected...Western and southwestern South Dakota into northern
   Nebraska

   Concerning...Severe Thunderstorm Watch 243...

   Valid 032056Z - 032300Z

   The severe weather threat for Severe Thunderstorm Watch 243
   continues.

   SUMMARY...The threat for severe thunderstorms continues for WW 243.
   The greatest near-term threat for severe hail and wind will lie from
   southwest South Dakota eastward along the SD/NE border.

   DISCUSSION...Isolated thunderstorms continue to develop across the
   WW 243 area both along a weakly convergent trough axis along western
   SD and in the vicinity of an outflow boundary that has stalled out
   north of the NE/SD border. The environment over the watch area
   remains supportive of a severe weather threat with severe hail
   already reported near Rapid City, SD. MLCAPE has increased slightly
   to 1500-2000 J/kg and deep layer shear remains supportive of
   organized convection. Discrete modes remain likely along the trough
   axis across western SD, but lingering MLCIN and weak forcing for
   ascent has limited the convective coverage so far. Additionally,
   storms that develop along the trough axis may be limited in eastward
   extent by the more stable cold pool air north of the outflow
   boundary (as indicated in mesoanalysis 0-3 km lapse rates). Despite
   these factors, a window for severe hail/wind remains with any storm
   that can become established. 

   Further south along the NE/SD border, weak forcing for ascent may
   limit the coverage of storms, but less mixed-layer inhibition will
   increase the potential for sustained, mature convection. Steeper
   low-level lapse rates will also support a better wind threat
   compared to areas further north along the trough axis. Given these
   considerations, this southern extent of the watch will see the
   better near-term potential for severe wind and hail.

   ..Moore.. 06/03/2020

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

   ATTN...WFO...FSD...LBF...UNR...CYS...

   LAT...LON   43810289 43860231 43180060 43279907 42799874 42159876
               41749937 41660143 41780229 41980262 42800321 43660342
               43810289