Mesoscale Discussion 1535
   NWS Storm Prediction Center Norman OK
   1033 PM CDT Fri Jul 19 2019

   Areas affected...far southeast MT...northeast WY and western/central
   SD

   Concerning...Severe potential...Watch possible 

   Valid 200333Z - 200500Z

   Probability of Watch Issuance...40 percent

   SUMMARY...Thunderstorms will increase in coverage and intensity the
   next few hours. The strongest storms may produce large hail. Trends
   will be monitored for possible watch issuance.

   DISCUSSION...Convection is developing late this evening in moist
   upslope flow coincident with warm advection atop a surface cold
   front and EML located around the 850-700 mb layer. The 00z UNR RAOB
   showed steep midlevel lapse rates above the EML with moderate
   instability across the MCD area. Effective shear is quite strong
   this evening, with 50+ kt indicated in 00z RAOBs and depicted by 03z
   mesoanalysis, which will support organized cells/clusters. Long,
   straight hodographs will increase potential for hail in the
   strongest storms, though the elevated nature of convection should
   temper damaging wind threat the next several hours. However, some
   guidance suggest some potential for upscale growth into forward
   propagating clusters/bowing segments overnight. If this occurs,
   damaging wind potential could increase after 06-07Z. Given a lack of
   strong upper level forcing, there is some uncertainty in the exact
   evolution of the threat and how widespread severe potential will be.
   Trends will continue to be monitored for possible watch issuance in
   the next couple of hours.

   ..Leitman/Thompson.. 07/20/2019

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

   ATTN...WFO...ABR...UNR...CYS...BYZ...

   LAT...LON   44070555 44810570 45370534 45760401 45920197 45769991
               45329933 44189967 43939980 43190176 42940307 42970460
               43550514 44070555