746  
ACUS48 KWNS 310923  
SWOD48  
SPC AC 310922  
 
DAY 4-8 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0322 AM CST TUE DEC 31 2024  
 
VALID 031200Z - 081200Z  
   
..DISCUSSION  
 
EXPANSIVE RIDGING IS FORECAST TO GRADUALLY SHIFT FROM THE PLAINS  
INTO THE MS VALLEY AND SOUTHEAST ON D4/FRIDAY, WITH STABLE  
CONDITIONS PREVAILING.  
 
A SHORTWAVE TROUGH IS EXPECTED TO PROGRESS FROM THE WESTERN GREAT  
BASIN THROUGH THE FOUR CORNERS AND INTO CENTRAL/SOUTHERN HIGH PLAINS  
ON D5/SATURDAY, CONTINUING EASTWARD ACROSS CENTRAL/SOUTHERN PLAINS  
AND MID/LOWER MS VALLEY ON D6/SUNDAY. SURFACE CYCLOGENESIS APPEARS  
PROBABLE OVER THE SOUTHERN HIGH PLAINS ON D5/SATURDAY AHEAD OF THE  
APPROACHING SHORTWAVE, WITH A WARM SECTOR CHARACTERIZED BY MID 60S  
DEWPOINTS LIKELY TO PRECEDE THE RESULTING SURFACE LOW AND ATTENDANT  
COLD FRONT. THUNDERSTORMS ARE POSSIBLE FROM CENTRAL TX/OK EASTWARD  
THROUGH THE LOWER MS VALLEY ON D6/SUNDAY, AS THE COLD FRONT  
INTERACTS WITH THE MODERATELY MOIST AND BUOYANT AIR WITHIN THE WARM  
SECTOR. DEEP-LAYER VERTICAL SHEAR IS EXPECTED TO BE STRONG ENOUGH TO  
SUPPORT ORGANIZED STORMS (I.E. GREATER THAN 40 KT FROM 0-6 KM).  
 
MID/UPPER LEVEL PATTERN IS SIMILAR BETWEEN THE EPS AND GEFS, BUT THE  
SURFACE PATTERN HAS NOTABLE DIFFERENCES, WITH MOST GEFS MEMBERS  
FAVORING A SLOWER AND MORE SOUTHERLY TRACK TO THE SURFACE LOW. THIS  
IS MATCHED BY THE DETERMINISTIC RUNS OF THE ECMWF AND GFS, WHILE THE  
CANADIAN SPLITS THE DIFFERENCE. EVEN THOUGH SOME SEVERE APPEARS  
PROBABLE, THESE DIFFERENCES LIMIT THE FORECAST CONFIDENCE, MAKING IT  
DIFFICULT TO ASCERTAIN THE MOST LIKELY CORRIDOR FOR SEVERE  
THUNDERSTORMS. ADDITIONALLY, ALL OF THE DETERMINISTIC GUIDANCE  
CONTINUES TO SHOW NOTABLE RUN-TO-RUN VARIABILITY. ALL OF THESE  
FACTORS COMBINED WITH THE EXTENDED RANGE OF THE POSSIBLE SEVERE  
(I.E. DAY 6) RESULT IN TOO MUCH UNCERTAINTY TO DELINEATE ANY RISK  
AREAS WITH THIS OUTLOOK.  
 
THE RISK FOR THUNDERSTORMS WILL LIKELY CONTINUE ALONG THE GULF COAST  
ON D7/MONDAY AS THIS SYSTEM CONTINUES EASTWARD. BY D8/TUESDAY, COLD  
AND DRY CONDITIONS ARE ANTICIPATED ACROSS THE ENTIRE CONUS.  
 
..MOSIER.. 12/31/2024  
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