627  
ACUS03 KWNS 311932  
SWODY3  
SPC AC 311930  
 
DAY 3 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0130 PM CST WED DEC 31 2025  
 
VALID 021200Z - 031200Z  
   
..NO SEVERE THUNDERSTORM AREAS FORECAST
 
 
   
..SUMMARY
 
 
GENERAL THUNDERSTORMS ARE FORECAST, MAINLY FRIDAY NIGHT INTO EARLY  
MORNING SATURDAY, ACROSS THE CENTRAL GULF COAST AND DEEP SOUTH, AS  
WELL AS ALONG COASTAL AREAS OF CENTRAL AND NORTHERN CALIFORNIA AND  
SOUTHWEST ORGEON.  
   
..LA/MS/AL VICINITY
 
 
A LOW-AMPLITUDE MIDLEVEL SHORTWAVE TROUGH IS FORECAST TO MOVE FROM  
THE SOUTH-CENTRAL PLAINS TOWARDS THE TN VALLEY ON FRIDAY. A SOMEWHAT  
STRONGER UPSTREAM SHORTWAVE TROUGH WILL MOVE QUICKLY  
EAST-SOUTHEASTWARD FROM THE GREAT BASIN TOWARD PARTS OF NORTH/EAST  
TX. A SURFACE LOW INITIALLY OVER NORTH TX IS EXPECTED TO MOVE  
EASTWARD TOWARD NORTHERN MS/AL BY FRIDAY NIGHT. INCREASING LOW-LEVEL  
MOISTURE WITHIN THE WARM SECTOR OF THIS LOW WILL ALLOW FOR MODEST  
DIURNAL DESTABILIZATION, WITH MLCAPE POTENTIALLY INCREASING TO  
NEAR/ABOVE 500 J/KG ACROSS PARTS OF LA/MS, IN ADVANCE OF A TRAILING  
COLD FRONT.  
 
STRENGTHENING DEEP-LAYER SHEAR WILL BECOME CONDITIONALLY FAVORABLE  
FOR ORGANIZED CONVECTION, BUT POTENTIAL FOR ROBUST SURFACE-BASED  
DEVELOPMENT MAY BE LIMITED BY POOR MIDLEVEL LAPSE RATES AND  
RELATIVELY MODEST LARGE-SCALE ASCENT WITHIN THE WARM SECTOR. IT  
STILL APPEARS THAT THE BULK OF ANY THUNDERSTORM DEVELOPMENT WILL BE  
SOMEWHAT ELEVATED AND OCCUR NEAR AND NORTH OF THE SURFACE WARM FRONT  
ACROSS NORTHERN MS/AL/GA AND SOUTHERN TN, PRIMARILY DURING THE  
EVENING AND OVERNIGHT. AT THIS TIME, ELEVATED BUOYANCY APPEARS  
INSUFFICIENT TO SUPPORT AN ORGANIZED SEVERE THREAT WITH THIS  
ACTIVITY. HOWEVER, IF CONFIDENCE INCREASES REGARDING DEVELOPMENT OF  
NEAR-SURFACE-BASED STORMS WITHIN THE WARM SECTOR OF THE  
EASTWARD-MOVING LOW, THEN SEVERE PROBABILITIES MAY EVENTUALLY BE  
NEEDED.  
   
..COASTAL NORTHERN CA/SOUTHWEST OR
 
 
A DEEP MID/UPPER-LEVEL TROUGH WILL GRADUALLY MOVE EASTWARD AND  
APPROACH THE PACIFIC COAST BY FRIDAY NIGHT, AS A STRONG JET BEGINS  
TO IMPINGE UPON AREAS OF CENTRAL/NORTHERN CA AND THE PACIFIC  
NORTHWEST. A DEEPENING SURFACE LOW ASSOCIATED WITH THIS TROUGH IS  
EXPECTED TO REMAIN OFFSHORE THROUGH SATURDAY MORNING. THE STRONGEST  
LOW-LEVEL FLOW (50+ KT AT 850 MB) WILL OCCUR WITHIN THE WARM  
CONVEYOR OF THIS CYCLONE, WHERE INSTABILITY IS EXPECTED TO REMAIN  
NEGLIGIBLE.  
 
LATE IN THE PERIOD, SOME COOLING ALOFT AND STEEPENING LAPSE RATES  
MAY APPROACH COASTAL AREAS OF CENTRAL/NORTHERN CA AND SOUTHWEST OR.  
THIS MAY ALLOW FOR DEVELOPMENT OF GENERALLY WEAK CONVECTION WITH  
SPROADIC LIGHTNING FLASHES. LOW-LEVEL FLOW IS FORECAST TO REMAIN  
RATHER STRONG (35-45 KT AT 850 MB) AS MIDLEVEL LAPSE RATES BEGIN TO  
STEEPEN, AND ANY LIGHTNING-PRODUCING CONVECTION COULD BE COINCIDENT  
WITH GUSTY WINDS. HOWEVER, ANY CONVECTIVE CONTRIBUTION TO  
DAMAGING-WIND POTENTIAL MAY BE LIMITED BY VERY MEAGER SURFACE-BASED  
BUOYANCY THROUGH THE END OF THE PERIOD.  
 
..DEAN.. 12/31/2025  
 

 
 
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