354  
ACUS01 KWNS 271625  
SWODY1  
SPC AC 271623  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
1123 AM CDT SAT SEP 27 2025  
 
VALID 271630Z - 281200Z  
   
..NO SEVERE THUNDERSTORM AREAS FORECAST
 
 
   
..SUMMARY
 
 
A SEVERE THREAT IS NOT EXPECTED TO DEVELOP ACROSS THE CONTINENTAL  
U.S. TODAY AND TONIGHT.  
   
..SYNOPSIS AND DISCUSSION
 
 
UPPER RIDGING CURRENTLY EXTENDS FROM THE ARKLATEX/LOWER MS VALLEY  
THROUGH THE CENTRAL HIGH PLAINS WITH UPPER LOWS FLANKING THIS  
RIDGING ON EACH SIDE. THE WESTERN UPPER LOW IS CENTERED OVER  
SOUTHERN CA/LOWER CO RIVER VALLEY. THIS LOW IS DISPLACED WELL SOUTH  
OF THE WESTERLIES ALONG THE US/CANADA BORDER AND IS NOT EXPECTED TO  
MOVE MUCH THROUGHOUT THE DAY. IN GENERAL, POOR LAPSE RATES SHOULD  
TEMPER THE BUOYANCY NEAR AND DOWNSTREAM OF THIS LOW (I.E. FROM THE  
LOWER CO VALLEY INTO AZ), MITIGATING THE OVERALL SEVERE POTENTIAL.  
THE GREATEST BUOYANCY IS EXPECTED ACROSS FAR EASTERN SOUTHERN CA AND  
SOUTHWESTERN AZ, NEAR THE CENTER OF THE UPPER LOW WHERE MID-LEVEL  
TEMPERATURES ARE COOLEST. HERE, A FEW STRONGER STORMS ARE POSSIBLE  
DURING THE AFTERNOON AND EVENING. SEVERE COVERAGE IS STILL EXPECTED  
TO BE TOO LOW TO MERIT ANY PROBABILITIES.  
 
THE EASTERN UPPER LOW, CURRENTLY CENTERED OVER THE SOUTHERN  
APPALACHIANS, HAS A MORE BROAD CIRCULATION THAN THE SOUTHERN CA LOW,  
WITH MOST GUIDANCE SUGGESTING IT DEVOLVES AND SHIFTS NORTHEASTWARD  
INTO THE MID-ATLANTIC THROUGHOUT THE PERIOD. MODERATE MID-LEVEL  
SOUTHWESTERLIES WILL PERSIST WITHIN THE EASTERN PERIPHERY OF THIS  
CYCLONE (I.E. FROM THE EASTERN CAROLINAS INTO NJ AND EASTERN PA)  
TODAY. BUOYANCY WILL BE MODEST, BUT THE STRONGER SHEAR FROM THESE  
SOUTHWESTERLIES COULD HELP SUPPORT A FEW STRONGER MULTICELLS CAPABLE  
OF DAMAGING GUSTS. OVERALL SEVERE COVERAGE IS STILL EXPECTED TO BE  
TOO LOW TO MERIT ANY PROBABILITIES.  
 
..MOSIER/HALBERT.. 09/27/2025  
 

 
 
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