Mesoscale Discussion 1380
   NWS Storm Prediction Center Norman OK
   0220 PM CDT Tue Jul 05 2022

   Areas affected...central into northeastern Montana

   Concerning...Severe potential...Watch possible 

   Valid 051920Z - 052045Z

   Probability of Watch Issuance...40 percent

   SUMMARY...The development of a couple of supercells posing a risk
   for severe hail and locally strong wind gusts appears possible in a
   corridor northeast of Lewistown into areas west of Glasgow by 4-6 PM
   MDT.  Trends are being monitored, but it is not clear that a severe
   weather watch will be needed.

   DISCUSSION...Low amplitude mid-level troughing is in the process of
   progressing across and northeast of the Canadian/northern U.S.
   Rockies, with an associated belt 40-50+ kt flow around the 500 mb
   level arcing across southwestern through northeastern Montana. 
   Forcing for ascent associated with at least one speed maximum
   embedded within this regime may be aiding ongoing deepening
   convective development to the west of the Lewistown area.  Aided by
   easterly inflow of increasingly unstable boundary layer, convection
   appears likely to gradually intensify and advect off the higher
   terrain during the next few hours.  

   As activity develops to the northeast of Lewistown, mixed-layer CAPE
   increasing in excess of 1000 J/kg may become supportive of more
   substantive intensification, and the evolution of a few supercells
   by 22-00Z.  This probably will be accompanied by the risk for severe
   hail and locally strong surface gusts.

   ..Kerr/Grams.. 07/05/2022

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

   ATTN...WFO...BYZ...GGW...TFX...

   LAT...LON   47181031 48250818 48440661 47690646 46780914 46621003
               47181031