649  
ACUS01 KWNS 240558  
SWODY1  
SPC AC 240556  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
1256 AM CDT THU JUL 24 2025  
 
VALID 241200Z - 251200Z  
 
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PARTS OF  
MICHIGAN AND THE LOWER GREAT LAKES INTO THE  
MIDWEST...CENTRAL/SOUTHERN PLAINS...AND HIGH PLAINS...  
   
..SUMMARY  
 
LOCALLY DAMAGING THUNDERSTORM WIND GUSTS WILL BE POSSIBLE FROM THE  
GREAT LAKES TO THE CENTRAL AND SOUTHERN PLAINS, MAINLY THIS  
AFTERNOON AND EVENING. ISOLATED SEVERE STORMS WILL ALSO POSE A RISK  
OF LARGE HAIL AND SEVERE WIND GUSTS OVER THE NORTHERN AND CENTRAL  
HIGH PLAINS.  
   
..LOWER MI INTO THE LOWER GREAT LAKES  
 
THE MARGINAL RISK HAS BEEN MAINTAINED ACROSS LOWER MI AND ADJACENT  
PARTS OF THE GREAT LAKES, THOUGH HIGHER WIND PROBABILITIES MAY  
EVENTUALLY BE NEEDED, IF CONFIDENCE INCREASES IN A SUFFICIENT  
COVERAGE OF ORGANIZED STORM DEVELOPMENT LATER TODAY INTO THIS  
EVENING.  
 
MULTIPLE LOW-AMPLITUDE MIDLEVEL VORTICITY MAXIMA (INCLUDING  
POTENTIALLY ONE OR MORE MCVS) WILL MOVE ACROSS PARTS OF THE GREAT  
LAKES REGION LATER TODAY, WITHIN A BROADER LARGE-SCALE UPPER-LEVEL  
TROUGH. A COLD FRONT WILL MOVE SOUTHEASTWARD ACROSS PARTS OF THE  
UPPER MIDWEST AND GREAT LAKES THROUGH THE DAY INTO THE EVENING.  
 
DIURNAL HEATING OF A RICHLY MOIST AIRMASS WILL RESULT IN THE  
DEVELOPMENT OF MODERATE BUOYANCY ALONG/AHEAD OF THE FRONT THIS  
AFTERNOON. THIS DESTABILIZATION WILL OCCUR BENEATH MODERATE  
LOW/MIDLEVEL SOUTHWESTERLY FLOW (25-40 KT IN THE 850-700 MB LAYER).  
THE RESULTING ENVIRONMENT WILL BE FAVORABLE FOR OUTFLOW-DOMINANT  
STORM CLUSTERS CAPABLE OF WIND DAMAGE.  
 
HOWEVER, DETAILS OF STORM COVERAGE AND TIMING REMAIN UNCERTAIN, DUE  
TO WEAK FRONTAL CONVERGENCE AND GENERALLY MODEST LARGE-SCALE ASCENT,  
OUTSIDE OF THE POTENTIAL INFLUENCE OF ANY MCVS. THERE IS SOME  
POTENTIAL FOR DEVELOPMENT RELATIVELY EARLY IN THE DAY ACROSS  
CENTRAL/NORTHERN LOWER MI, WHEN SOMEWHAT STEEPER MIDLEVEL LAPSE  
RATES MAY STILL BE IN PLACE. THIS SCENARIO MAY BE THE GREATEST  
RELATIVE THREAT FOR ORGANIZED STORMS, THOUGH GUIDANCE VARIES  
REGARDING THE COVERAGE OF STORMS THROUGH EARLY AFTERNOON. OTHERWISE,  
MIDLEVEL TEMPERATURES WILL TEND TO WARM BY LATER AFTERNOON, THOUGH  
ANY STRONGER CELLS/CLUSTERS WOULD STILL BE CAPABLE OF PRODUCING WIND  
DAMAGE AS LOW-LEVEL LAPSE RATES STEEPEN.  
 
STORMS MAY SPREAD INTO PARTS OF WESTERN NY FROM ONTARIO LATE THIS  
EVENING. WHILE A GENERAL WEAKENING TREND IS EXPECTED BY THIS TIME,  
STRONG TO LOCALLY DAMAGING GUSTS CANNOT BE RULED OUT LATE TONIGHT  
BEFORE CONVECTION SUBSIDES.  
   
..NORTHERN MO/IL/IN INTO CENTRAL/EASTERN KS AND NORTHERN OK  
 
SCATTERED STORM DEVELOPMENT IS EXPECTED THIS AFTERNOON AND EVENING  
FROM CENTRAL/EASTERN KS AND NORTHERN OK INTO PARTS OF NORTHERN  
MO/IL/IN, ALONG AND AHEAD OF A COLD FRONT. SOMEWHAT ENHANCED  
LOW/MIDLEVEL FLOW WILL BE PRESENT ACROSS NORTHERN IL/IN EARLY IN THE  
DAY, BUT GRADUAL WEAKENING OF FLOW IS GENERALLY FORECAST WITH TIME.  
FARTHER SOUTHWEST, FLOW IS FORECAST TO REMAIN RATHER WEAK INTO  
NORTHERN MO AND THE CENTRAL/SOUTHERN PLAINS. AS A RESULT, STORM  
ORGANIZATION MAY TEND TO BE LIMITED, BUT MODERATE TO STRONG BUOYANCY  
AND LARGE PW (POTENTIALLY 2 INCHES OR GREATER) WILL SUPPORT A THREAT  
OF LOCALIZED DOWNBURSTS. ONE OR MORE SMALL CLUSTERS COULD DEVELOP  
AND POSE A THREAT FOR MORE CONCENTRATED WIND DAMAGE, BUT CONFIDENCE  
IN THE DETAILS OF THIS POTENTIAL SCENARIO REMAINS LOW.  
   
..HIGH PLAINS  
 
MODERATE BUOYANCY IS EXPECTED TO DEVELOP ACROSS PARTS OF THE CENTRAL  
AND NORTHERN HIGH PLAINS THIS AFTERNOON. LARGE-SCALE ASCENT WILL  
GENERALLY BE NEBULOUS IN THE WAKE OF A DEPARTING SHORTWAVE TROUGH,  
BUT AT LEAST ISOLATED STORM DEVELOPMENT IS POSSIBLE NEAR THE  
ADJACENT HIGHER TERRAIN. EFFECTIVE SHEAR OF 30-40 KT WILL SUPPORT  
SOME STORM ORGANIZATION. INITIAL DISCRETE CELLS MAY POSE A THREAT OF  
HAIL, WHILE SOME OUTFLOW AMALGAMATION COULD EVENTUALLY OCCUR, WITH A  
THREAT OF STRONG TO LOCALLY SEVERE GUSTS SPREADING EASTWARD INTO THE  
EVENING.  
 
FARTHER SOUTH, SCATTERED TO NUMEROUS THUNDERSTORMS ARE EXPECTED INTO  
PARTS OF THE SOUTHERN HIGH PLAINS. DEEP-LAYER SHEAR WILL BE WEAK  
ACROSS THIS REGION, BUT LOCALIZED STRONG TO SEVERE OUTFLOW GUSTS  
WILL BE POSSIBLE.  
 
..DEAN/THORNTON.. 07/24/2025  
 
 
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