572  
ACUS03 KWNS 301930  
SWODY3  
SPC AC 301929  
 
DAY 3 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0129 PM CST TUE DEC 30 2025  
 
VALID 011200Z - 021200Z  
   
..NO SEVERE THUNDERSTORM AREAS FORECAST  
 
   
..SUMMARY  
 
ISOLATED THUNDERSTORMS ARE POSSIBLE ON NEW YEAR'S DAY ACROSS PARTS  
OF SOUTHERN CALIFORNIA AND ARIZONA.  
   
..SOUTHERN CA TO AZ  
 
A MID/UPPER-LEVEL SHORTWAVE TROUGH WILL MOVE ACROSS PARTS OF  
SOUTHERN CA THURSDAY MORNING, BEFORE DAMPENING AS IT SHIFTS EASTWARD  
ACROSS PARTS OF THE DESERT SOUTHWEST AND FOUR CORNERS REGION LATER  
IN THE PERIOD. COOLING ALOFT ATOP MODESTLY INCREASING LOW-LEVEL  
MOISTURE WILL SUPPORT SOME EARLY-DAY THUNDERSTORM POTENTIAL ACROSS  
COASTAL SOUTHERN CA.  
 
GUIDANCE CONTINUES TO VARY REGARDING THE STRENGTH, TRAJECTORY, AND  
MAGNITUDE OF ATTENDANT FLOW FIELDS OF THIS SYSTEM AS IT APPROACHES  
THE COAST. THE SOMEWHAT STRONGER AND FARTHER SOUTH SOLUTIONS (SUCH  
AS THE 12Z NAM/RRFS) DEPICT POTENTIAL FOR STRONG STORM DEVELOPMENT  
OFFSHORE, WHICH COULD AFFECT NEAR-COASTAL AREAS OF SOUTHERN CA  
DURING THE MORNING BEFORE WEAKENING. OTHER GUIDANCE (SUCH AS THE 12Z  
ECMWF) HAS TRENDED NORTHWARD, BRINGING STRONGER MIDLEVEL FLOW ACROSS  
SOUTHERN CA, BUT ALSO GREATER DISPLACEMENT BETWEEN SUBSTANTIAL  
COOLING ALOFT AND THE MORE FAVORABLE LOW-LEVEL MOISTURE. IN GENERAL,  
CONFIDENCE IN SUFFICIENT STRENGTHENING OF FLOW WITHIN THIS WEAK  
BUOYANCY REGIME REMAINS TOO LOW TO INCLUDE SEVERE PROBABILITIES.  
 
UNCERTAINTY REGARDING THE EVOLUTION OF THE SHORTWAVE EXTENDS  
DOWNSTREAM INTO PARTS OF THE DESERT SOUTHWEST, BUT AN AREA OF  
MODESTLY ENHANCED LOW-LEVEL MOISTURE ACROSS SOUTHWEST AZ COULD  
SUPPORT ISOLATED STORM DEVELOPMENT LATER IN THE DAY INTO THE  
EVENING, AS SOME COOLING ALOFT OVERSPREADS THE REGION.  
 
..DEAN.. 12/30/2025  
 
 
CLICK HERE TO GO TO PREVIOUS BULLETINS.
The Nexlab SPC Page
Main Text Page