613  
ACUS01 KWNS 282001  
SWODY1  
SPC AC 282000  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0300 PM CDT SAT JUN 28 2025  
 
VALID 282000Z - 291200Z  
 
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF  
PENNSYLVANIA AND NEW YORK AS WELL AS ACROSS PORTIONS OF THE NORTHERN  
PLAINS....  
   
..SUMMARY
 
 
SCATTERED SEVERE THUNDERSTORMS ARE POSSIBLE ACROSS PORTIONS OF THE  
UPPER MIDWEST INTO THE NORTH-CENTRAL GREAT PLAINS. ALL SEVERE  
HAZARDS ARE POSSIBLE CENTERED ON SOUTHERN MINNESOTA AND EASTERN  
SOUTH DAKOTA. SCATTERED DAMAGING GUSTS ARE POSSIBLE ACROSS PARTS OF  
NEW YORK INTO PENNSYLVANIA.  
   
..20Z UPDATE
 
 
THE MAIN CHANGE WITH THIS UPDATE IS TO EXPAND THE HAIL THREAT  
FARTHER NORTH AND WEST INTO PORTIONS OF EAST-CENTRAL NORTH DAKOTA  
AND WEST-CENTRAL MINNESOTA. HERE, STRONG INSTABILITY AND  
DEVELOPING/ONGOING THUNDERSTORMS WILL BE CAPABLE OF PRODUCING LARGE  
HAIL. SEE MCD #1492 FOR ADDITIONAL METEOROLOGICAL DISCUSSION.  
 
ELSEWHERE, ONLY MINOR CHANGES WERE MADE TO THE ONGOING FORECAST.  
 
..MARSH.. 06/28/2025  
   
PREV DISCUSSION
 
/ISSUED 1126 AM CDT SAT JUN 28 2025/  
   
..EASTERN SD/MN/WI
 
 
CURRENT RADAR LOOPS SHOW A PERSISTENT MCS SLOWLY WEAKENING ACROSS  
SOUTHERN MN. THIS FEATURE HAS DRIVEN AN ASSOCIATED OUTFLOW BOUNDARY  
INTO NORTHWEST IA AND EASTERN SD. MORNING MODEL SOLUTIONS ARE IN  
GENERAL AGREEMENT THAT THE LOW-LEVEL AIR MASS WILL RAPIDLY RECOVER  
IN THE WAKE OF THE MCS, LEADING TO RAPID AND INTENSE THUNDERSTORM  
DEVELOPMENT BY LATE AFTERNOON OVER WESTERN MN. IT IS UNCLEAR IF THE  
MODELS ARE HANDLING THE LINGERING EFFECTS OF THE MORNING CONVECTION,  
BUT THE EVENTUAL RE-DEVELOPMENT OF STORMS POSES RISKS OF TORNADOES,  
VERY LARGE HAIL, AND DAMAGING WINDS. AN UPGRADE TO ENH RISK OVER  
PARTS OF CENTRAL/SOUTHERN MN FOR THIS EVENING WAS CONSIDERED, BUT  
WILL DEFER TO THE 20Z OUTLOOK, AFTER FURTHER EVALUATION OF THE  
ONGOING CONVECTION AND TRENDS IN DESTABILIZATION.  
   
..WESTERN SD VICINITY
 
 
FULL SUN WILL LEAD TO STRONG HEATING AND DEEP MIXING ACROSS MUCH OF  
EASTERN WY TODAY. HIGH-BASED CONVECTION WILL DEVELOP BY LATE  
AFTERNOON IN THIS REGION AND SPREAD EASTWARD INTO A PROGRESSIVELY  
MORE MOIST AND UNSTABLE AIR MASS OVER WESTERN SD. SCATTERED INTENSE  
STORMS ARE EXPECTED TO DEVELOP, POSING A RISK OF LARGE HAIL AND  
DAMAGING WIND GUSTS. THESE STORMS MAY PERSIST THROUGH THE EVENING  
AND GROW UPSCALE, WITH A RISK OF DAMAGING WINDS INTO SOUTHERN  
SD/NORTHERN NE.  
   
..NY/PA/MID-ATLANTIC
 
 
A SURFACE COLD FRONT IS SAGGING SOUTHWARD INTO NY AND WESTERN PA  
TODAY. THUNDERSTORMS HAVE BEGUN TO INTENSIFY ALONG/AHEAD OF THE  
FRONT, WITH LOCALLY DAMAGING WIND GUSTS EXPECTED THROUGH THE  
AFTERNOON. LOW CLOUDS ARE LIMITING HEATING/DESTABILIZATION OVER  
EASTERN NY/PA AND THE MID-ATLANTIC REGION. HOWEVER, HEATING SHOULD  
COMMENCE BY MID/LATE AFTERNOON, ALLOWING STORMS APPROACHING FROM THE  
WEST TO MAINTAIN A DAMAGING WIND THREAT INTO THE EARLY EVENING.  
 

 
 
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