591  
ACUS11 KWNS 050043  
SWOMCD  
SPC MCD 050043  
MTZ000-050215-  
 
MESOSCALE DISCUSSION 1887  
NWS STORM PREDICTION CENTER NORMAN OK  
0743 PM CDT MON AUG 04 2025  
 
AREAS AFFECTED...PARTS OF CENTRAL MONTANA  
 
CONCERNING...SEVERE THUNDERSTORM WATCH 573...  
 
VALID 050043Z - 050215Z  
 
THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 573  
CONTINUES.  
 
SUMMARY...THUNDERSTORMS WILL CONTINUE INCREASING IN INTENSITY AND  
COVERAGE WHILE SPREADING NORTHEASTWARD ACROSS SEVERE THUNDERSTORM  
WATCH 573. SEVERE WIND GUSTS AND ISOLATED LARGE HAIL ARE THE MAIN  
CONCERNS.  
 
DISCUSSION...THE LATEST WATER-VAPOR IMAGERY INDICATES STRENGTHENING  
MIDLEVEL ASCENT IMPINGING ON WESTERN/CENTRAL MT THIS EVENING --  
PRECEDING A COMPACT/NEGATIVE-TILT MIDLEVEL TROUGH OVER THE NORTHERN  
ROCKIES. REGIONAL VWP DATA SHOWS STRENGTHENING MIDLEVEL  
SOUTHWESTERLY FLOW AHEAD OF THE TROUGH, WHICH IS CONTRIBUTING TO  
AROUND 40 KT OF DEEP-LAYER SHEAR. IN RESPONSE TO THESE FACTORS,  
THUNDERSTORMS WILL CONTINUE INCREASING IN INTENSITY AND COVERAGE  
WHILE SPREADING/DEVELOPING NORTHEASTWARD ACROSS CENTRAL MT -- WITHIN  
SEVERE THUNDERSTORM WATCH 573. THE STRENGTHENING LARGE-SCALE ASCENT,  
WELL-MIXED BOUNDARY LAYER, AND FAVORABLE DEEP-LAYER SHEAR IS  
FAVORING THE DEVELOPMENT OF A LOOSELY ORGANIZED BROKEN BAND OF  
STORMS, CAPABLE OF PRODUCING SEVERE OUTFLOW WINDS. HOWEVER, THE  
WEST-SOUTHWESTERLY DEEP-LAYER SHEAR VECTORS (ORTHOGONAL TO THE  
DEVELOPING LARGER-SCALE COLD POOL) ARE ALSO SUPPORTING SEMI-DISCRETE  
SUPERCELL STRUCTURES ALONG THE EVOLVING CONVECTIVE BAND, AS WELL AS  
AHEAD OF THIS ACTIVITY. LARGE HAIL IS ALSO A CONCERN WITH THESE MORE  
DISCRETE STORMS.  
 
..WEINMAN.. 08/05/2025  
   
..PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT
 
 
ATTN...WFO...BYZ...GGW...TFX...  
 
LAT...LON 45750798 46670854 46910922 46881019 46901159 47141242  
47381260 47761249 48661120 49041032 49080936 48820820  
48310719 47580653 46260630 45670660 45660727 45750798  
 
MOST PROBABLE PEAK WIND GUST...65-80 MPH  
MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN  
 
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