822  
WWUS20 KWNS 232145  
SEL0  
SPC WW 232145  
MTZ000-240400-  
 
URGENT - IMMEDIATE BROADCAST REQUESTED  
SEVERE THUNDERSTORM WATCH NUMBER 620  
NWS STORM PREDICTION CENTER NORMAN OK  
350 PM MDT SUN AUG 23 2026  
 
THE NWS STORM PREDICTION CENTER HAS ISSUED A  
 
* SEVERE THUNDERSTORM WATCH FOR PORTIONS OF  
EASTERN MONTANA  
 
* EFFECTIVE THIS SUNDAY AFTERNOON AND EVENING FROM 350 PM UNTIL  
1000 PM MDT.  
 
* PRIMARY THREATS INCLUDE...  
SCATTERED DAMAGING WINDS AND ISOLATED SIGNIFICANT GUSTS TO 75  
MPH POSSIBLE  
ISOLATED LARGE HAIL EVENTS TO 1.5 INCHES IN DIAMETER POSSIBLE  
 
SUMMARY...SCATTERED HIGH-BASED THUNDERSTORMS WILL SPREAD EASTWARD  
FROM CENTRAL INTO EASTERN MONTANA THROUGH LATE EVENING. A FEW  
SUPERCELL STRUCTURES WITH LARGE HAIL WILL BE POSSIBLE INITIALLY.  
THE THREAT FOR SEVERE OUTFLOW GUSTS OF 60-75 MPH WILL INCREASE AS  
STORMS CLUSTER OVER TIME.  
 
THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 100  
STATUTE MILES EAST AND WEST OF A LINE FROM 55 MILES NORTH NORTHEAST  
OF GLASGOW MT TO 80 MILES SOUTHEAST OF BILLINGS MT. FOR A COMPLETE  
DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE UPDATE  
(WOUS64 KWNS WOU0).  
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...  
 
REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE  
FAVORABLE FOR SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH AREA.  
PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR THREATENING  
WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS AND POSSIBLE  
WARNINGS. SEVERE THUNDERSTORMS CAN AND OCCASIONALLY DO PRODUCE  
TORNADOES.  
 

 
 
OTHER WATCH INFORMATION...CONTINUE...WW 617...WW 618...WW 619...  
 
AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT TO  
1.5 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 65 KNOTS. A  
FEW CUMULONIMBI WITH MAXIMUM TOPS TO 450. MEAN STORM MOTION VECTOR  
27030.  
 
...THOMPSON  
 
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