952  
ACUS01 KWNS 291232  
SWODY1  
SPC AC 291230  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0730 AM CDT SUN JUN 29 2025  
 
VALID 291300Z - 301200Z  
 
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE UPPER  
MIDWEST TO THE CENTRAL HIGH PLAINS...  
   
..SUMMARY
 
 
ISOLATED TO SCATTERED STRONG TO SEVERE THUNDERSTORMS ARE POSSIBLE  
FROM THE UPPER GREAT LAKES INTO THE CENTRAL HIGH PLAINS. WIND IS THE  
PRIMARY RISK, THOUGH HAIL IS EXPECTED ACROSS PORTIONS OF THE HIGH  
PLAINS.  
   
..UPPER GREAT LAKES TO THE CENTRAL HIGH PLAINS
 
 
BELT OF STRONGER WESTERLIES WILL REMAIN CONFINED TO THE  
U.S.-CANADIAN BORDER STATES AS A MID- TO UPPER-LEVEL TROUGH SHIFTS  
EAST FROM THE MT/ND VICINITY INTO THE UPPER MIDWEST LATE. A SURFACE  
FRONT IS ANALYZED THIS MORNING FROM THE UPPER MIDWEST, WHERE IT IS  
ILL DEFINED AND MODULATED BY CONVECTIVE OUTFLOW, SOUTHWESTWARD INTO  
NORTHERN KS AND ARCING WEST-NORTHWEST INTO THE CENTRAL HIGH PLAINS.  
SOME EASTWARD MOVEMENT IS FORECAST DURING THE DAY ACROSS THE UPPER  
MIDWEST WHEREAS THE FRONTAL SEGMENT OVER THE CENTRAL GREAT PLAINS  
WILL BECOME STATIONARY THIS AFTERNOON. THIS BOUNDARY AND ASSOCIATED  
COMPOSITE OUTFLOW WILL SERVE AS THE PRIMARY FOCUS FOR RENEWED  
SHOWER/THUNDERSTORM ACTIVITY THIS AFTERNOON INTO TONIGHT.  
 
A DECAYING MCS OVER WESTERN IA/SOUTHEAST NE THIS MORNING WILL  
FURTHER WEAKEN AND AN ONGOING CORRIDOR OF WEAK THUNDERSTORMS EXTENDS  
SOUTHEAST FROM THE MCS THROUGH THE LOWER MO VALLEY. REMOVED FROM  
CLOUD DEBRIS, STRONG HEATING OF A SEASONABLY MOIST BOUNDARY LAYER  
WILL RESULT IN STRONG DESTABILIZATION FROM WI SOUTHWESTWARD INTO KS,  
WHERE 2000-3500 J/KG MLCAPE IS FORECAST BY MID AFTERNOON. THE  
AFOREMENTIONED DISPLACEMENT OF THIS REGION FROM STRONGER MID AND  
HIGH-LEVEL FLOW WILL LIMIT POTENTIAL FOR GREATER STORM ORGANIZATION.  
HOWEVER, ISOLATED TO SCATTERED THUNDERSTORMS WILL LIKELY EVOLVE INTO  
SEVERAL SMALL-SCALE BANDS AND CLUSTERS FROM THE WESTERN GREAT LAKES  
INTO THE LOWER MO VALLEY POSING MAINLY A WIND RISK WITH THE STRONGER  
STORMS. STRONGER HEATING FARTHER WEST OVER CENTRAL KS WESTWARD INTO  
PARTS OF THE CENTRAL HIGH PLAINS WILL RESULT IN STEEP LOW TO  
MID-LEVEL TROPOSPHERIC LAPSE RATES. EVAPORATIVE COOLING OF STRONGER  
WATER-LADEN DOWNDRAFTS WILL YIELD A THREAT FOR SEVERE GUSTS ACROSS  
THE CENTRAL GREAT PLAINS INTO THE LOWER MO VALLEY. HAIL MAY  
ACCOMPANY THE STRONGER CORES, BUT THIS RISK WILL BE LIMITED BY A  
DEEP MELTING LAYER AND A MULTICELLULAR STORM MODE. A COUPLE OF  
CLUSTERS MAY PERSIST THROUGH THE EVENING AND INTO THE OVERNIGHT AS  
THIS ACTIVITY SHIFTS SOUTHWARD, PERHAPS INTO SOUTHEAST KS AND  
NORTHERN OK LATE.  
 
ANOTHER CORRIDOR WHERE STRONG/SEVERE CONVECTION IS EXPECTED IS  
ACROSS THE HIGH PLAINS FROM EASTERN WY INTO NORTHEAST CO. NORTHWEST  
FLOW IS FORECAST TO STRENGTHEN ACROSS THE NORTHERN HIGH PLAINS ALONG  
THE BACK SIDE OF THE TROUGH. ISOLATED SUPERCELLS ARE EXPECTED TO  
DEVELOP ALONG THE SYNOPTIC FRONT THAT WILL BE DRAPED ACROSS THIS  
REGION. FORECAST SOUNDINGS DO NOT EXHIBIT STRONG BUOYANCY, BUT  
MODEST SHEAR AND MOIST PROFILES FAVOR ORGANIZED UPDRAFTS THAT SHOULD  
SPREAD SOUTHEAST TOWARD THE NE PANHANDLE. LARGE HAIL AND WIND ARE  
EXPECTED.  
   
..MID ATLANTIC STATES
 
 
A MOIST AND MODERATELY UNSTABLE AIRMASS WILL FAVOR ISOLATED TO  
SCATTERED THUNDERSTORMS DEVELOPING DURING THE AFTERNOON ACROSS THE  
REGION. HIGH PW AND STEEPENED SURFACE TO 850-MB LAPSE RATES AMIDST  
WEAK SHEAR WILL RESULT IN RELATIVELY DISORGANIZED INDIVIDUAL STORMS  
AND SMALLER CLUSTERS. LOCALIZED STRONG TO SEVERE GUSTS (50-60 MPH)  
MAY RESULT AND YIELD POCKETS OF WIND DAMAGE WITH THE STRONGER CORES.  
 
..SMITH/BROYLES.. 06/29/2025  
 

 
 
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