236  
ACUS01 KWNS 300543  
SWODY1  
SPC AC 300541  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
1241 AM CDT MON MAR 30 2026  
 
VALID 301200Z - 311200Z  
 
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF  
THE UPPER MISSISSIPPI VALLEY...  
   
..SUMMARY
 
 
A FEW SEVERE THUNDERSTORMS WITH LARGE HAIL, ARE EXPECTED ACROSS  
PARTS OF THE UPPER MISSISSIPPI RIVER VALLEY LATE TONIGHT INTO EARLY  
TUESDAY MORNING. ISOLATED STRONG TO MARGINALLY SEVERE STORMS COULD  
OCCUR FURTHER EAST INTO PARTS OF LOWER MICHIGAN EARLY TUESDAY  
MORNING.  
   
..UPPER MISSISSIPPI VALLEY/GREAT LAKES
 
 
TODAY AND TONIGHT AT MID-LEVELS IN THE MISSISSIPPI VALLEY,  
WEST-NORTHWESTERLY FLOW WILL GRADUALLY TRANSITION TO  
WEST-SOUTHWESTERLY, AS A SUBTLE SHORTWAVE RIDGE MOVES EASTWARD INTO  
THE GREAT LAKES. IN RESPONSE, LOW-LEVEL MOISTURE ADVECTION WILL  
STRENGTHEN OVER THE CENTRAL U.S., AS A 50 TO 60 KNOT 850 MB JET  
DEVELOPS ACROSS THE CENTRAL PLAINS. THE NORTHERN EDGE OF THE  
LOW-LEVEL JET WILL BE LOCATED IN THE UPPER MISSISSIPPI VALLEY BY  
THIS EVENING. STRONG LIFT ASSOCIATED WITH THE JET WILL LIKELY RESULT  
IN CONVECTIVE INITIATION DURING THE MID TO LATE EVENING FROM  
NORTHEAST IOWA INTO SOUTHERN WISCONSIN. RAP FORECAST SOUNDINGS AT  
06Z IN THE LA CROSSE VICINITY HAVE MUCAPE INCREASING INTO THE 2000  
TO 2500 J/KG RANGE WITH EFFECTIVE SHEAR FORECAST TO BE NEAR 40  
KNOTS. IN ADDITION, 700-500 MB LAPSE RATES ARE FORECAST TO APPROACH  
8.5 C/KM. THIS ENVIRONMENT WILL LIKELY SUPPORT LARGE HAIL WITH  
ELEVATED SUPERCELLS THAT DEVELOP IN THE LATE EVENING AND EARLY  
OVERNIGHT PERIOD. HAILSTONES GREATER THAN 2 INCHES IN DIAMETER WILL  
BE POSSIBLE.  
 
FURTHER EAST INTO LOWER MICHIGAN, CONVECTIVE INITIATION IS EXPECTED  
TO OCCUR BY LATE IN THE PERIOD. COMPARED WITH AREAS TO THE WEST,  
MUCAPE AND LAPSE RATES IN LOWER MICHIGAN ARE FORECAST TO BE WEAKER.  
FOR THIS REASON, THE HAIL THREAT THERE IS EXPECTED TO BE MORE WIDELY  
SPACED AND MARGINAL.  
 
..BROYLES/SQUITIERI.. 03/30/2026  
 

 
 
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