Severe Storm Outlook Narrative (AC)
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554 ACUS11 KWNS 201938 SWOMCD SPC MCD 201938 MTZ000-202045- Mesoscale Discussion 1345 NWS Storm Prediction Center Norman OK 0238 PM CDT Thu Jun 20 2024 Areas affected...West Central Montana Concerning...Severe potential...Watch unlikely Valid 201938Z - 202045Z Probability of Watch Issuance...20 percent SUMMARY...Thunderstorm development over the mountains has increased over the last half hour, with the potential for a supercell or two to develop in Central MT. Isolated hail and damaging winds are possible, especially with isolated convection that moves eastward into the better buoyancy and shear. WW issuance is not likely due to uncertainty in spatial coverage of severe threats. DISCUSSION...Thunderstorms are increasing in coverage along the mountains in far western MT, and a more mature thunderstorm has developed over Judith Basin county. Due to proximity to the upper trough, RAP forecast profiles show cold temperatures aloft supportive of SBCAPE > 1000 J/kg. Deep layer shear over Central and Eastern MT are in the range of 40-50kts, decreasing towards the west over the higher terrain. Any convection that tracks further east into Central MT should encounter better combinations of shear and buoyancy, resulting in an isolated threat for 1+ inch hail and 60+ MPH wind gusts. However, due to uncertainty in spatial coverage of organized severe storms, WW issuance is not expected at this time. ..Halbert/Lyons/Hart.. 06/20/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...BYZ...GGW...TFX...MSO... LAT...LON 46841349 47991355 48831361 48991326 48751257 47661225 47391140 47471071 47720948 47830872 47540826 46990815 46520826 46310857 46120922 45960985 45681080 45801233 46151329 46841349