732  
ACUS01 KWNS 281302  
SWODY1  
SPC AC 281300  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0700 AM CST SUN DEC 28 2025  
 
VALID 281300Z - 291200Z  
 
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM EASTERN  
ILLINOIS TO INDIANA...  
   
..SUMMARY  
 
SCATTERED SEVERE THUNDERSTORMS ARE POSSIBLE OVER ILLINOIS AND  
INDIANA THIS AFTERNOON THROUGH THE EVENING. SEVERE WIND GUSTS  
CAPABLE OF WIND DAMAGE AND A COUPLE OF TORNADOES ARE THE PRIMARY  
THREATS.  
   
..MID MS VALLEY EAST THROUGH IN-OH-WESTERN PA  
 
WATER-VAPOR IMAGERY THIS MORNING SHOWS A MID-LEVEL LOW NEAR THE  
MT/ND BORDER WITH A TROUGH INTO THE CENTRAL ROCKIES/SANGRE DE  
CRISTOS. THIS MID-LEVEL LOW WILL MOVE INTO THE CENTRAL GREAT LAKES  
BY EARLY MONDAY MORNING. STRONG SOUTHWESTERLY 500-MB FLOW (80 KT)  
EXTENDING FROM THE BASE OF THE TROUGH THROUGH THE LOWER MO VALLEY  
AND OH VALLEY WILL FEATURE AN INTENSIFYING 110-KT JET REACHING THE  
MO-IL BORDER THIS EVENING BEFORE FURTHER STRENGTHENING TO 130 KT  
OVER OH BY THE END OF THE PERIOD.  
 
A SURFACE LOW OVER EASTERN KS WILL DEEPEN RAPIDLY THROUGH TONIGHT AS  
IT MOVES TO LAKE HURON. A FRONTAL ZONE EXTENDING EAST-NORTHEAST  
THROUGH THE SOUTHERN GREAT LAKES THIS MORNING WILL SERVE AS THE  
NORTHERN EDGE OF THE MOIST SECTOR. A COLD FRONT INITIALLY OVER  
KS-OK WILL SURGE SOUTH-EAST. SOUTHERLY LOW-LEVEL FLOW ACROSS THE  
MOIST SECTOR WILL MAINTAIN A FETCH OF SEASONABLY HIGH 58-62 DEG F  
DEWPOINTS IMMEDIATELY AHEAD OF THE FRONT/LOW.  
 
A RAIN SHIELD WITH EMBEDDED THUNDERSTORMS THIS MORNING FROM NORTHERN  
MO INTO THE SOUTHERN GREAT LAKES COULD FEATURE A STRONGER STORM OR  
TWO THROUGH MIDDAY, BUT THE PRIMARY SEVERE RISK WILL LIKELY FOCUS  
THIS AFTERNOON THROUGH TONIGHT. MODEL GUIDANCE INDICATES THE CAP  
WILL ERODE NEAR THE EVOLVING TRIPLE POINT AND COLD FRONT BY MID-LATE  
AFTERNOON. UPWARDS OF 500-1000 J/KG MLCAPE IS POSSIBLE ACROSS PARTS  
OF CENTRAL INTO EASTERN IL WITH BUOYANCY TAPERING WITH EAST EXTENT  
ACROSS THE OH VALLEY. A SOUTHWARD-DEVELOPING CONVECTIVE BAND IS  
FORECAST TO EVOLVE LATE THIS AFTERNOON THROUGH THE EARLY EVENING.  
LONG HODOGRAPHS AND STRONG 2-3 KM FLOW WILL FAVOR A RISK FOR SEVERE  
GUSTS WITH THE MORE INTENSE STORMS AND SURGES WITH THE MATURING  
BAND. MODELS INDICATE THE WIND-DAMAGE THREAT MAY PERSIST ACROSS THE  
OH VALLEY/SOUTHERN GREAT LAKES TONIGHT DESPITE MEAGER INSTABILITY.  
THE TORNADO RISK APPEARS HIGHEST WITH CELLS THAT CAN DEVELOP NEAR  
THE INSTABILITY AXIS AND MATURE BEFORE EITHER DESTRUCTIVE  
INTERFERENCE OF THE LARGER-SCALE COLD POOL OVERWHELMS CELLULAR MODE,  
AND/OR THIS ACTIVITY MOVES FARTHER EAST INTO LESSENING INSTABILITY.  
 
..SMITH/WEINMAN.. 12/28/2025  
 
 
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