906  
ACUS01 KWNS 261248  
SWODY1  
SPC AC 261246  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0746 AM CDT THU MAR 26 2026  
 
VALID 261300Z - 271200Z  
 
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF  
THE MIDWEST/OHIO VALLEY...  
   
..SUMMARY  
 
SCATTERED SEVERE THUNDERSTORMS ARE EXPECTED THIS AFTERNOON AND  
EVENING ACROSS PARTS OF THE MIDWEST AND OHIO VALLEY. LARGE TO VERY  
LARGE HAIL, A FEW TORNADOES, AND SEVERE/DAMAGING WINDS ALL APPEAR  
LIKELY.  
   
..MID MISSISSIPPI VALLEY INTO THE MIDWEST/OHIO VALLEY  
 
UPPER RIDGING WILL REMAIN SUPPRESSED OVER THE SOUTHWEST AND SOUTHERN  
PLAINS TODAY AS RATHER STRONG WESTERLY MID/UPPER-LEVEL JETS  
OVERSPREAD THE UPPER MIDWEST/GREAT LAKES. A WEAK MID-LEVEL SHORTWAVE  
TROUGH THAT HAS ENCOURAGED OCCASIONAL LIGHTING FLASHES WITH  
CONVECTION ACROSS THE NE PANHANDLE EARLIER THIS MORNING WILL  
APPROACH THE MID MS VALLEY/MIDWEST BY LATE THIS AFTERNOON. A COLD  
FRONT IS FORECAST TO MOVE SOUTHWARD THROUGH THE DAY ACROSS  
IL/IN/SOUTHERN LOWER MI/OH AS A WEAK SURFACE REFLECTION DEVELOPS  
EASTWARD INTO CENTRAL PA THROUGH THIS EVENING. A PARTIALLY  
MODIFIED/SHALLOW GULF AIRMASS WILL STREAM NORTHWARD AHEAD OF THIS  
FRONT, WITH SURFACE DEWPOINTS GENERALLY EXPECTED TO REMAIN IN THE  
MID 50S TO NO MORE THAN LOW 60S.  
 
CURRENT EXPECTATIONS ARE FOR THUNDERSTORMS TO QUICKLY DEVELOP ALONG  
THE LENGTH OF THE FRONT FROM CENTRAL IL EASTWARD INTO IN, SOUTHERN  
LOWER MI, AND NORTHERN OH BY 19-22Z AS DIURNAL HEATING ERODES  
LINGERING CONVECTIVE INHIBITION. EVEN THOUGH LOW-LEVEL MOISTURE  
SHOULD REMAIN FAIRLY SHALLOW/LIMITED AHEAD OF THE FRONT, A NARROW  
CORRIDOR OF 1000-1500 J/KG OF MLCAPE (LOCALLY STRONGER POSSIBLE) IS  
FORECAST TO BE PRESENT BY MID TO LATE AFTERNOON GIVEN SUFFICIENT  
DAYTIME HEATING AND STEEPENING MID-LEVEL LAPSE RATES. STRONG FLOW OF  
50-60+ KT IN THE 700-500 MB LAYER AND RELATED DEEP-LAYER SHEAR OF  
SIMILAR MAGNITUDE WILL SUPPORT ORGANIZED UPDRAFTS AND SUPERCELLS  
WITH THIS INITIAL DEVELOPMENT. LARGE TO VERY LARGE HAIL (2+ INCHES  
IN DIAMETER POSSIBLE) SHOULD OCCUR AS LONG AS A SUPERCELL MODE CAN  
BE MAINTAINED.  
 
A FAIRLY QUICK TRANSITION TO MORE LINEAR STRUCTURES APPEARS LIKELY  
GIVEN THE FRONTAL FORCING, WITH AN INCREASING THREAT FOR SCATTERED  
TO NUMEROUS SEVERE/DAMAGING WINDS AS ONE OR MORE CLUSTERS SPREADS  
EAST-SOUTHEASTWARD ACROSS MUCH OF THE OH VALLEY INTO WESTERN/CENTRAL  
PA THROUGH THE LATE AFTERNOON AND EVENING. GIVEN THE FORECAST  
STRENGTH OF THE LOW TO MID-LEVEL FLOW, ISOLATED GUSTS OF 75+ MPH MAY  
OCCUR. THERE IS A THREAT FOR A FEW TORNADOES AS WELL WITH BOTH  
SUPERCELLS AND EMBEDDED MESOCIRCULATIONS WITHIN THE LINEAR CLUSTERS,  
ALTHOUGH A WELL-MIXED BOUNDARY LAYER SHOULD INCREASE LCLS THIS  
AFTERNOON AS SURFACE TEMPERATURES GENERALLY WARM INTO THE 70S AND  
80S. SOME GUIDANCE SUGGESTS A LOCALLY GREATER THREAT FOR TORNADOES  
(PERHAPS A COUPLE STRONG) MAY EXIST ACROSS PARTS OF NORTHERN/CENTRAL  
IN/OH WITH ANY SUPERCELLS THAT CAN BE MAINTAINED ALONG/AHEAD OF THE  
COLD FRONT, AS LOW-LEVEL SHEAR SHOULD BE GREATER ACROSS THESE AREAS  
IN ASSOCIATION WITH A 35-50 KT WEST-SOUTHWESTERLY LOW-LEVEL JET.  
HOWEVER, CONFIDENCE IN THIS SCENARIO OCCURRING WAS TOO LOW TO  
INCLUDE HIGHER TORNADO PROBABILITIES WITH THIS UPDATE.  
 
FARTHER WEST ACROSS THE MID MS VALLEY (MO INTO EASTERN KS), THERE IS  
LOWER CONFIDENCE IN WARM SECTOR THUNDERSTORM DEVELOPMENT THIS  
AFTERNOON AND EVENING DUE TO THE PRESENCE OF A STRONGER CAP.  
HOWEVER, ELEVATED CONVECTION MAY OCCUR ALONG/BEHIND THE COLD FRONT  
THIS EVENING, WITH STRONG DEEP-LAYER SHEAR AND SUFFICIENT MUCAPE  
CONDITIONALLY SUPPORTING SUPERCELLS WITH MAINLY A THREAT FOR LARGE  
HAIL. HAVE MADE ONLY MINOR CHANGES TO THE SLIGHT RISK ACROSS THIS  
AREA BASED ON LATEST GUIDANCE TRENDS.  
 
..GLEASON/KERR.. 03/26/2026  
 
 
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