Storm Prediction Center Mesoscale Discussion 1337

   Mesoscale Discussion 1337
   NWS Storm Prediction Center Norman OK
   0356 PM CDT Fri Jun 26 2026

   Areas affected...portions of central Montana and far northern
   Wyoming

   Concerning...Severe potential...Watch possible 

   Valid 262056Z - 262300Z

   Probability of Watch Issuance...60 percent

   SUMMARY...A few thunderstorms with large hail and severe gusts may
   occur across portions of central Montana and far northern Wyoming. A
   watch may be needed.

   DISCUSSION...A large trough is in place across the northwestern
   CONUS with an attendant jet max ejecting across the northern
   Rockies, and associated lee troughing as brought moisture westward
   to the High Plains of Montana and Wyoming. With this overlap in lift
   and moisture, storms have developed along the high terrain of
   southern/central Montana and northwest Wyoming. Due to the jet max,
   deep layer shear should be sufficient for supercells once convection
   moves onto the High Plains.

   With the strong deep layer shear and low freezing levels, large hail
   may occur with the strongest storms. As the afternoon and evening
   progress, storms may cluster, and the deeply-mixed boundary layer
   and strong low-level flow may promote a threat for severe gusts. One
   potential limiting factor may be widespread cloud cover and
   associated inhibition, which may limit downward momentum transfer
   needed for severe winds. Despite this, a watch may be needed to
   cover this threat.

   ..Supinie/Guyer.. 06/26/2026

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

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

   LAT...LON   44840984 45311087 45971135 47451115 47921018 47920915
               47580809 46790712 46100688 45250729 44750855 44840984 

   MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 90 MPH
   MOST PROBABLE PEAK WIND GUST...55-70 MPH
   MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN