943  
ACUS11 KWNS 051722  
SWOMCD  
SPC MCD 051721  
MTZ000-WYZ000-051945-  
 
MESOSCALE DISCUSSION 1566  
NWS STORM PREDICTION CENTER NORMAN OK  
1221 PM CDT SAT JUL 05 2025  
 
AREAS AFFECTED...CENTRAL MONTANA TO NORTHERN WYOMING  
 
CONCERNING...SEVERE POTENTIAL...WATCH LIKELY  
 
VALID 051721Z - 051945Z  
 
PROBABILITY OF WATCH ISSUANCE...80 PERCENT  
 
SUMMARY...WEAK CONVECTION DEVELOPING WITHIN THE NORTHERN ROCKIES  
WILL INTENSIFY OVER THE NEXT FEW HOURS AS IT MOVES INTO CENTRAL  
MONTANA AND NORTHERN WYOMING. SEVERE THUNDERSTORM WATCH ISSUANCE IS  
PROBABLE EARLY THIS AFTERNOON AS STORMS POSE AN INCREASING SEVERE  
THREAT.  
 
DISCUSSION...LATEST GOES VISIBLE IMAGERY SHOWS CLUSTERS OF AGITATED  
CUMULUS AND A FEW WEAK THUNDERSTORMS DEVELOPING ACROSS FAR NORTHWEST  
WY AND WITHIN THE MOUNTAIN RANGES OF CENTRAL MT. ASCENT ASSOCIATED  
WITH AN APPROACHING UPPER LOW COMBINED WITH CONTINUED DAYTIME  
HEATING WILL PROMOTE FURTHER DEVELOPMENT/MATURATION OF CONVECTION  
OVER THE NEXT SEVERAL HOURS. LATEST FORECAST GUIDANCE SUGGESTS THAT  
LINGERING INHIBITION SHOULD BE LARGELY REMOVED AS TEMPERATURES CLIMB  
INTO THE UPPER 70S TO LOW 80S. THIS IS EXPECTED TO OCCUR BETWEEN  
18-20 UTC AND SHOULD HAPPEN AS WEAK/SHALLOW CONVECTION OVERSPREADS  
SOMEWHAT RICHER LOW-LEVEL MOISTURE IN PLACE AT LOWER ELEVATIONS  
ACROSS CENTRAL MT TO NORTHERN WY. THIS WILL RESULT IN AN OVERALL  
INTENSIFICATION OF THUNDERSTORMS DURING THIS TIME FRAME. MODERATE  
FLOW ASSOCIATED WITH THE MID-LEVEL WAVE WILL SUPPORT EFFECTIVE SHEAR  
VALUES ON THE ORDER OF 30-40 KNOTS. AS SUCH, A FEW SUPERCELLS APPEAR  
LIKELY WITH AN ATTENDANT RISK FOR LARGE HAIL (POSSIBLY AS LARGE AS 2  
INCHES). THIS THREAT APPEARS MOST PROBABLE ALONG THE MT/WY BORDER  
WHERE LOW-LEVEL MOISTURE IS RELATIVELY HIGHER AHEAD OF A WEAK  
OUTFLOW BOUNDARY AND DEWPOINTS REMAIN IN THE MID/UPPER 50S. WITH  
TIME, INCREASING BOUNDARY-LAYER DEPTH THROUGH THE LATE AFTERNOON  
SHOULD PROMOTE GREATER COLD POOL PRODUCTION AND GRADUAL UPSCALE  
GROWTH WITH AN INCREASING SEVERE WIND THREAT. GIVEN THESE CONCERNS,  
WATCH ISSUANCE IS ANTICIPATED IN THE COMING HOURS AS CONVECTION  
CONTINUES TO DEVELOP.  
 
..MOORE/HART.. 07/05/2025  
   
..PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT  
 
ATTN...WFO...UNR...BYZ...GGW...RIW...TFX...  
 
LAT...LON 44000610 43620651 43550733 43770801 43980841 44540870  
47160899 47580891 47890861 48100805 48130760 48100700  
47850667 45490585 44920578 44390589 44000610  
 
MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 95 MPH  
MOST PROBABLE PEAK WIND GUST...65-80 MPH  
MOST PROBABLE PEAK HAIL SIZE...1.50-2.50 IN  
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