282  
ACUS01 KWNS 201231  
SWODY1  
SPC AC 201230  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0730 AM CDT TUE OCT 20 2026  
 
VALID 201300Z - 211200Z  
   
..NO SEVERE THUNDERSTORM AREAS FORECAST
 
 
   
..SUMMARY
 
 
ORGANIZED SEVERE THUNDERSTORMS APPEAR UNLIKELY THROUGH TONIGHT.  
   
..GREAT BASIN INTO THE SOUTHWEST AND SOUTHERN/CENTRAL PLAINS
 
 
ISOLATED SHOWERS AND THUNDERSTORMS ONGOING THIS MORNING ACROSS PARTS  
OF SOUTHERN/CENTRAL NM MAY DEVELOP DOWNSTREAM TODAY OVER PORTIONS OF  
THE SOUTHERN/CENTRAL PLAINS AS MODEST SOUTHWESTERLY MID-LEVEL FLOW  
PERSISTS. AS A CLOSED MID/UPPER-LEVEL LOW DIGS SOUTHWARD OFF THE  
WEST COAST, CONVECTION CAPABLE OF PRODUCING OCCASIONAL LIGHTNING IS  
ALSO FORECAST TO DEVELOP THIS AFTERNOON THROUGH TONIGHT ACROSS PARTS  
OF THE GREAT BASIN AND SOUTHWEST. LOW-LEVEL MOISTURE IS FORECAST TO  
FURTHER INCREASE THROUGH THE PERIOD OVER THE LOWER CO RIVER VALLEY  
AND SOUTHERN/CENTRAL AZ.  
 
WHILE A STRONGER THUNDERSTORM OR TWO MAY DEVELOP ACROSS SOUTHEAST AZ  
THIS AFTERNOON WITH DAYTIME HEATING AIDED BY OROGRAPHIC EFFECTS,  
BETTER LARGE-SCALE ASCENT ASSOCIATED WITH A STRONG SOUTHWESTERLY  
MID/UPPER-LEVEL JET WILL LIKELY BE DELAYED UNTIL LATE TONIGHT/EARLY  
WEDNESDAY MORNING. GREATER COVERAGE OF THUNDERSTORMS MAY BE REALIZED  
TOWARDS THE END OF THE PERIOD ACROSS CENTRAL/NORTHERN AZ, BUT IN A  
WEAK THERMODYNAMIC ENVIRONMENT. THE OVERALL SEVERE HAIL/WIND THREAT  
ACROSS THE SOUTHWEST CURRENTLY APPEARS LOWER AND EVEN MORE ISOLATED  
THAN YESTERDAY, SO HAVE NOT INTRODUCED ANY SEVERE PROBABILITIES WITH  
THIS UPDATE.  
 
..GLEASON/KERR.. 10/20/2026  
 

 
 
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