792  
ACUS03 KWNS 241928  
SWODY3  
SPC AC 241928  
 
DAY 3 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0228 PM CDT FRI JUL 24 2026  
 
VALID 261200Z - 271200Z  
 
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER THE UPPER  
MISSISSIPPI VALLEY INTO UPPER MIDWEST...  
   
..SUMMARY
 
 
SEVERE THUNDERSTORMS CAPABLE OF MAINLY LARGE HAIL AND DAMAGING WINDS  
ARE POSSIBLE FROM THE UPPER MISSISSIPPI VALLEY AND GREAT LAKES INTO  
PORTIONS OF THE MID MISSOURI VALLEY ON SUNDAY AND SUNDAY NIGHT.  
   
..SYNOPSIS
 
 
ENHANCED MID-LEVEL FLOW WILL ROUND THE CENTRAL US RIDGE D3/SUNDAY,  
OVERSPREADING PORTIONS OF THE MIDWEST AND GREAT LAKES REGIONS. ALONG  
WITH THE INCREASING FLOW, SEVERAL SHORTWAVE DISTURBANCES WILL SHIFT  
ACROSS THE REGION. AT THE SURFACE, A LOW WILL DEVELOP ACROSS THE  
NORTHERN PLAINS/UPPER MIDWEST WITH A SURFACE FRONT MOVING THROUGH  
THE NORTHERN PLAINS/MIDWEST BY THE EVENING.  
   
..UPPER MISSISSIPPI VALLEY INTO THE GREAT LAKES
 
 
BENEATH STRONG UPPER-LEVEL RIDGING AND A VERY MOIST AIR MASS WITH  
DEW POINTS IN THE 60S TO MID 70S, AN EML PLUME WILL ADVECT EASTWARD  
ACROSS THE HIGH PLAINS INTO THE MIDWEST/GREAT LAKES REGION. THIS  
WILL RESULT IN A VERY VOLATILE AND STRONGLY UNSTABLE BUT LARGELY  
CAPPED AIR MASS. WHILE FORCING FOR ASCENT WILL INCREASE, LACK OF  
DISCERNIBLE SURFACE FEATURES AND STRENGTH OF THE CAPPING INVERSION  
LEADS TO LOW CONFIDENCE IN THE EXACT EVOLUTION OF THUNDERSTORM  
DEVELOPMENT. HI-RES GUIDANCE DOES SUGGEST THAT A FEW ISOLATED  
SUPERCELLS MAY DEVELOP. A CONDITIONAL THREAT FOR LARGE TO VERY LARGE  
HAIL, DAMAGING WIND, AND PERHAPS A TORNADO WILL EXIST WITH ANY  
STORMS THAT CAN BECOME ROOTED WITHIN THE BOUNDARY LAYER, GIVEN THE  
PRESENCE OF 35-50 KT DEEP-LAYER SHEAR AND THE FAVORABLE UNSTABLE AIR  
MASS.  
 
AS THE FRONT SHIFTS SOUTH AND EAST THROUGH THE AFTERNOON/EVENING AND  
FORCING FOR ASCENT INCREASES, STORMS MAY DEVELOP AS FAR WEST AS THE  
EASTERN DAKOTAS/NEBRASKA. IT SEEMS PROBABLE THAT A THUNDERSTORM  
COMPLEX COULD DEVELOP ACROSS SOME PORTION OF THE UPPER MISSISSIPPI  
VALLEY, THOUGH CONFIDENCE IN THE EXACT CORRIDOR REMAINS LOW. THIS  
WILL POSE A CONDITIONAL THREAT FOR A MORE FOCUSED CORRIDOR OF  
DAMAGING WIND POTENTIAL.  
 
..THORNTON.. 07/24/2026  
 

 
 
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