683  
ACUS01 KWNS 261934  
SWODY1  
SPC AC 261933  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0233 PM CDT FRI SEP 26 2025  
 
VALID 262000Z - 271200Z  
 
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THROUGH THIS  
EVENING FROM CENTRAL INTO SOUTHEAST ARIZONA...  
   
..SUMMARY
 
 
OCCASIONAL LARGE HAIL (1-2 INCHES IN DIAMETER) AND OUTFLOW GUSTS OF  
60-70 MPH WILL BE POSSIBLE THROUGH THIS EVENING FROM CENTRAL INTO  
SOUTHEAST ARIZONA.  
   
..CENTRAL/SOUTHEAST AZ THROUGH THIS EVENING
 
 
A CLOSED MID-UPPER LOW NOW OVER SOUTHEAST CA WILL MOVE LITTLE  
THROUGH SATURDAY MORNING, AND THE LEFT-EXIT REGION OF AN EMBEDDED  
JET CORE WILL FOCUS OVER CENTRAL/SOUTHEAST AZ THROUGH THIS EVENING.  
SURFACE HEATING IN CLOUD BREAKS IS BOOSTING TEMPERATURES INTO THE  
MID 80S TO LOWER 90S WHERE DEWPOINTS ARE IN THE LOW-MID 60S, WHICH  
IS CONTRIBUTING TO MODERATE BUOYANCY (MLCAPE OF 1500-2000 J/KG).  
NEW STORMS WILL CONTINUE TO DEVELOP THROUGH THE AFTERNOON ALONG THE  
SOUTHERN AND WESTERN FLANKS OF THE ONGOING CONVECTION FROM THE  
MOGOLLON RIM INTO SOUTHEAST AZ. SUFFICIENTLY LONG  
HODOGRAPHS/DEEP-LAYER SHEAR AND THE MODERATE BUOYANCY WILL SUPPORT A  
MIX OF CLUSTERS AND SUPERCELLS CAPABLE OF PRODUCING OCCASIONAL LARGE  
HAIL (1-2 INCHES IN DIAMETER) AND OUTFLOW GUSTS OF 60-70 MPH.  
FAVORABLE STORM INTERACTIONS COULD PRODUCE A BRIEF TORNADO, THOUGH  
THIS THREAT WILL REMAIN HIGHLY LOCALIZED.  
   
..SOUTHEAST ATLANTIC COAST THIS AFTERNOON
 
 
THUNDERSTORM DEVELOPMENT IS UNDERWAY FROM NORTH FL ACROSS SOUTHEAST  
GA INTO THE CAROLINAS, DOWNSTREAM FROM A WEAK MIDLEVEL TROUGH OVER  
TN/AL. A WESTERLY COMPONENT TO THE NEAR-SURFACE WINDS SUGGESTS THE  
SEA BREEZE WILL REMAIN CLOSE TO THE COAST THROUGH THE AFTERNOON AND  
WILL SERVE TO FOCUS ADDITIONAL THUNDERSTORM DEVELOPMENT. HOWEVER,  
REGIONAL 18Z SOUNDINGS REVEALED POOR MIDLEVEL LAPSE RATES AND (AT  
BEST) MODEST MIDLEVEL SHEAR, WHICH SUGGEST THAT THE THREAT FOR WIND  
DAMAGE REMAINS TOO LOW TO INTRODUCE SEVERE WIND PROBABILITIES.  
 
..THOMPSON.. 09/26/2025  
   
PREV DISCUSSION
 
/ISSUED 1121 AM CDT FRI SEP 26 2025/  
   
..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.  
 

 
 
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