670  
ACUS01 KWNS 261622  
SWODY1  
SPC AC 261621  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
1121 AM CDT FRI SEP 26 2025  
 
VALID 261630Z - 271200Z  
 
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF  
SOUTHERN AND CENTRAL AZ INTO FAR SOUTHWESTERN NM...  
   
..SUMMARY
 
 
STRONG THUNDERSTORMS WITH HAIL AND STRONG TO MARGINALLY SEVERE GUSTS  
ARE POSSIBLE TODAY ACROSS PARTS OF SOUTHERN AND CENTRAL ARIZONA INTO  
FAR SOUTHWESTERN NEW MEXICO.  
   
..SOUTHWEST
 
 
A WELL-DEFINED UPPER LOW CONTINUES TO PROGRESS SLOWLY EASTWARD  
ACROSS SOUTHERN CA. GIVEN ITS DISPLACEMENT WELL SOUTH OF THE PRIMARY  
WESTERLIES ALONG THE US/CANADA BORDER, ONLY LIMITED EASTWARD  
PROGRESSION OF THIS LOW IS ANTICIPATED, WITH SOME POTENTIAL IT  
STALLS IN OVER THE LOWER CO RIVER VALLEY VICINITY. AMPLE MOISTURE  
REMAINS IN PLACE AHEAD OF THIS UPPER LOW, AND THE RESULTING  
COMBINATION OF PERSISTENT LARGE-SCALE ASCENT ASSOCIATED WITH THE LOW  
AND THIS MOISTURE WILL RESULT IN SCATTERED TO NUMEROUS THUNDERSTORMS  
ACROSS MUCH OF THE SOUTHERN GREAT BASIN AND SOUTHWEST. BUOYANCY WILL  
BE LIMITED THROUGHOUT MUCH OF THIS REGION, TEMPERING THE OVERALL  
UPDRAFT STRENGTH AND STORM SEVERITY.  
 
THE ONLY EXCEPTION IS FROM CENTRAL INTO SOUTHEAST AZ AND FAR  
SOUTHWEST NM WHERE GREATER LOW-LEVEL MOISTURE EXISTS SOUTH OF A WARM  
FRONT THAT EXTENDS NORTHWESTWARD ACROSS THE REGION TO A SURFACE LOW  
OVER THE LOWER CO VALLEY. ADDITIONAL THUNDERSTORM DEVELOPMENT IS  
ANTICIPATED IN THIS VICINITY OF THIS FRONT THIS AFTERNOON, WHERE THE  
GREATER LOW-LEVEL MOISTURE (I.E. LOW 60S DEWPOINTS) WILL CONTRIBUTE  
TO AFTERNOON MLCAPE AROUND 1500 TO 2000 J/KG. MODERATE LOW TO  
MID-LEVEL SOUTHWESTERLIES WILL HELP INCREASE DEEP-LAYER SHEAR  
VALUES, PARTICULARLY ALONG THE WARM FRONT WHERE SURFACE  
SOUTHEASTERLIES ARE POSSIBLE. THESE ENVIRONMENTAL CONDITIONS SUPPORT  
THE POTENTIAL FOR ROTATING STORMS CAPABLE OF PRODUCING LARGE HAIL.  
STEEP LOW-LEVEL LAPSE RATES THROUGHOUT THE WARM SECTOR SUGGEST THE  
POTENTIAL FOR DAMAGING GUSTS EXISTS AS WELL. A LOW-PROBABILITY  
TORNADO THREAT MAY MATERIALIZE ALONG THE WARM FRONT, WITH THE  
MAGNITUDE OF THE THREAT DEPENDENT ON THE STRENGTH OF THE SURFACE  
SOUTHEASTERLIES.  
   
..ELSEWHERE
 
 
BROAD UPPER TROUGHING EXTENDING FROM THE NORTHEAST THROUGH THE LOWER  
MS VALLEY WILL CONTRIBUTE TO SCATTERED THUNDERSTORMS ACROSS MUCH OF  
THE SOUTHEAST AND MID-ATLANTIC. LIMITED BUOYANCY SHOULD TEMPER THE  
OVERALL STORM INTENSITY, ALTHOUGH A STRONG STORM OR TWO IS POSSIBLE  
WITHIN THE MOIST ENVIRONMENT OVER THE CAROLINAS. A FEW THUNDERSTORMS  
ARE ALSO POSSIBLE ACROSS NORTHERN MN AS A COLD FRONT MOVES THROUGH  
THE REGION OVERNIGHT.  
 
..MOSIER/THORNTON.. 09/26/2025  
 

 
 
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