Storm Prediction Center Mesoscale Discussion 1478

   Mesoscale Discussion 1478
   NWS Storm Prediction Center Norman OK
   0555 PM CDT Fri Jul 03 2026

   Areas affected...Eastern Montana

   Concerning...Severe potential...Watch unlikely 

   Valid 032255Z - 040100Z

   Probability of Watch Issuance...20 percent

   SUMMARY...Isolated severe wind gusts and hail will be possible this
   evening across parts of eastern Montana. The threat is expected to
   be marginal, and additional weather watch issuance appears unlikely.

   DISCUSSION...Latest surface analysis shows a surface trough over
   eastern Montana, along which low-level convergence is maximized.
   Near the convergence axis, surface dewpoints are in the upper 50s F
   and MLCAPE is estimated by the RAP in the 1000 to 1500 J/kg range. A
   broken line of strong thunderstorms is ongoing along the western
   edge of the stronger instability, and appears to be supported by a
   mid-level shortwave trough approaching from the west. The Glasgow
   and Billings WSR-88D VWPs have 25 to 30 knots of deep-layer shear.
   In addition, RAP forecast soundings show steep low to mid-level
   lapse rates. This environment could be enough for an isolated severe
   threat with strong wind gusts and hail possible.

   ..Broyles/Gleason.. 07/03/2026

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

   ATTN...WFO...BIS...UNR...BYZ...GGW...

   LAT...LON   48680407 48890447 48970511 48960564 48670642 47990701
               46920790 46360803 45750785 45450751 45250696 45120627
               45110587 45080539 45150454 45580407 46450395 48240399
               48680407 

   MOST PROBABLE PEAK WIND GUST...UP TO 60 MPH
   MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN