447  
ACUS01 KWNS 300536  
SWODY1  
SPC AC 300535  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
1235 AM CDT TUE SEP 30 2025  
 
VALID 301200Z - 011200Z  
   
..NO SEVERE THUNDERSTORM AREAS FORECAST  
 
   
..SUMMARY  
 
SEVERE STORMS ARE UNLIKELY TODAY AND TONIGHT.  
   
..SYNOPSIS  
 
AN EXPANSIVE MID-LEVEL RIDGE WILL PERSIST FROM THE MS VALLEY INTO  
THE UPPER GREAT LAKES A PAIR OF TCS AND AN UPPER LOW INTENSIFY OFF  
THE ATLANTIC SEABOARD. AS THESE STORMS ARE FORECAST TO RECURVE, DRY  
OFFSHORE FLOW IS EXPECTED IN THEIR WAKE OVER THE ENTIRETY OF THE  
EASTERN CONUS AS SURFACE HIGH PRESSURE INTENSIFIES AND MOVE SOUTH  
OUT OF EASTERN CANADA. THE COOLER AND DRIER SURFACE CONDITIONS  
SHOULD LIMIT THUNDERSTORM POTENTIAL OUTSIDE OF COASTAL FL AND THE  
SOUTHERN APPALACHIANS WHERE SHALLOW BUOYANT PROFILES REMAIN.  
 
A LARGE UPPER LOW WILL GRADUALLY EXPAND OVER THE WESTERN THIRD OF  
THE CONUS THROUGH TONIGHT. WHILE SOUTHWESTERLY FLOW ALOFT IS  
FORECAST TO INCREASE, DRY SURFACE CONDITIONS ARE EXPECTED AS REMNANT  
MOISTURE IS SCOURED EAST. SCATTERED THUNDERSTORMS REMAIN POSSIBLE  
OVER THE INTERMOUNTAIN WEST AND ALONG A LEE TROUGH ACROSS THE  
CENTRAL HIGH PLAINS. THE PRESENCE OF ONLY MODEST SURFACE MOISTURE  
AND POOR LAPSE RATES WILL LIMIT DIURNAL DESTABILIZATION ACROSS MUCH  
OF THE CONUS. WHILE AN ISOLATED STRONGER STORM REMAINS POSSIBLE  
OVER THE NORTHERN GREAT BASIN AND HIGH PLAINS, MEAGER BUOYANCY AND  
MODEST OVERLAP WITH STRONGER VERTICAL SHEAR WILL LARGELY PRECLUDE  
SEVERE POTENTIAL.  
 
..LYONS/MOORE.. 09/30/2025  
 
 
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