096  
FXUS63 KIWX 252323  
AFDIWX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE NORTHERN INDIANA  
723 PM EDT WED JUN 25 2025  
   
KEY MESSAGES
 
 
- A HEAT ADVISORY REMAINS IN EFFECT THROUGH 8 PM ET FOR NORTHERN INDIANA  
AND NORTHWEST OHIO. PEAK HEAT INDICES OF 95 TO 100 DEGREES  
ARE EXPECTED TODAY.  
 
- HEAT INDICES WEDNESDAY THROUGH FRIDAY WILL BE 90 TO 100, WITH  
THE HIGHEST VALUES EXPECTED ALONG AND SOUTH OF US 30.  
CUMULATIVE EFFECTS OF LONG-DURATION HEAT WILL LIKELY CAUSE  
SIGNIFICANT IMPACTS.  
 
- NEAR RECORD WARM OVERNIGHT LOW TEMPERATURES IN THE LOW TO MID  
70S THROUGH THE WEEKEND WILL PROVIDE LITTLE TO NO RELIEF FROM  
THE HEAT, ESPECIALLY FOR VULNERABLE POPULATIONS.  
 
- NUMEROUS SHOWERS AND THUNDERSTORMS ARE EXPECTED THIS AFTERNOON  
AND EVENING, ESPECIALLY EAST OF US 31. A FEW STORMS MAY BECOME  
STRONG TO SEVERE WITH DAMAGING WINDS AND HEAVY RAINFALL.  
 

 
   
DISCUSSION
 
 
ISSUED AT 222 PM EDT WED JUN 25 2025  
 
A STALLED FRONTAL BOUNDARY DRAPED ALONG THE INDIANA-MICHIGAN  
STATELINE WILL BRING CHANCES FOR NUMEROUS SHOWERS AND STORMS THIS  
AFTERNOON AND EVENING. HIGHS IN THE UPPER 80S AND DEWPOINTS ONCE  
AGAIN IN THE LOW TO MID 70S WILL RESULT IN AIRMASS DESTABILIZATION  
THIS AFTERNOON. VISIBLE SATELLITE IMAGERY DEPICTS A FIELD OF  
SCATTERED CUMULUS CLOUDS ACROSS NORTHEAST INDIANA AND NORTHWEST  
OHIO. WHILE THERE IS A LACK OF SHEAR, LOW LEVEL LAPSE RATES AND  
SURFACE BASED CAPE OF 2500+ J/KG WILL FUEL THUNDERSTORM  
DEVELOPMENT THIS AFTERNOON AND EVENING. STORMS HAVE ALREADY  
INITIATED IN CENTRAL INDIANA AS OF 2 PM ET, AND COVERAGE SHOULD  
EXPAND ACROSS NORTHEAST INDIANA AND NORTHWEST OHIO WITHIN THE  
NEXT FEW HOURS. THE ENVIRONMENT IS MORE 'CAPPED' (STABLE) OVER  
THE WESTERN HALF OF OUR FORECAST AREA TODAY SO EXPECT THE  
SHOWER/STORM ACTIVITY TO BE GREATER ALONG AND EAST OF US 31.  
BECAUSE OF THE SLOW STORM MOTION AND POSSIBILITY FOR OUTFLOW  
BOUNDARY INTERACTION, ISOLATED INSTANCES OF FLASH FLOODING WILL  
BE POSSIBLE TODAY. A FEW STORMS COULD BECOME STRONG TO SEVERE;  
SPC HAS OUR AREA IN A MARGINAL RISK (LEVEL 1 OF 5) FOR SEVERE  
WEATHER. ALONGSIDE THE HEAVY RAIN THREAT, STORMS COULD BE  
CAPABLE OF PRODUCING GUSTY TO DAMAGING WINDS.  
 
THE UPPER LEVEL RIDGE RESPONSIBLE FOR THE HOT AND HUMID CONDITIONS  
OVER THE PAST SEVERAL DAYS PERSISTS OVER MUCH OF THE EASTERN  
CONUS. A HEAT ADVISORY REMAINS IN EFFECT UNTIL 8 PM ET TODAY,  
ALTHOUGH STORMS (AND ASSOCIATED OUTFLOW BOUNDARIES) MAY BRING  
TEMPORARY COOLING THIS AFTERNOON/EVENING. ADDITIONAL HEAT  
HEADLINES COULD BE NEEDED IN THE COMING DAYS AS THE HOT AND  
OPPRESSIVELY HUMID CONDITIONS PERSIST. IF YOU CONSIDER HIGHS IN  
THE 80S TO BE A REPRIEVE FROM THE HEAT, THEN THE NEXT FEW DAYS  
MAY SEEM 'COOLER'. HIGHS WILL BE IN THE UPPER 80S TODAY THROUGH  
THE WEEKEND WITH LOWS IN THE LOW TO MID 70S. WHILE IT WON'T BE  
AS HOT AS WHAT WE EXPERIENCED WHEN THE EXTREME HEAT WARNING WAS  
IN EFFECT EARLIER IN THE WEEK, WITH SUCH MUGGY, UNCOMFORTABLE  
CONDITIONS AT NIGHT, THERE WILL BE LITTLE RELIEF FROM THE HEAT  
THROUGH THE WEEKEND. STAY COOL AND STAY HYDRATED!  
 
THE UPPER LEVEL RIDGE PATTERN FLATTENS OUT THIS WEEK AND LOOKS TO  
POTENTIALLY BREAK DOWN OVER THE WEEKEND. BY EARLY NEXT WEEK, IT IS  
POSSIBLE WE GET A REPRIEVE FROM THE HEAT AND TEMPERATURES DROP BACK  
TO NEAR NORMAL LEVELS. ADDITIONAL RAIN/STORM CHANCES WILL BE  
POSSIBLE OVER THE WEEKEND BUT CONFIDENCE IS LOW.  
 

 
   
AVIATION /00Z TAFS THROUGH 00Z THURSDAY/
 
 
ISSUED AT 714 PM EDT WED JUN 25 2025  
 
CONTINUED HEAT AND MOISTURE MAKING FOR UNSTABLE CONDITIONS,  
ESPECIALLY DIURNALLY. CHANCES OF SHOWERS AND PERHAPS A  
THUNDERSTORM OR TWO OVERNIGHT BUT THE BETTER CHANCES COME AFTER  
18Z THU FOR BOTH TAF SITES. OUTSIDE OF MVFR/IFR VSBYS IN  
THUNDERSTORM RAINS, VFR IS EXPECTED THROUGH THE TAF PERIOD.  
 

 
   
IWX WATCHES/WARNINGS/ADVISORIES
 
 
IN...HEAT ADVISORY UNTIL 8 PM EDT /7 PM CDT/ THIS EVENING FOR  
INZ005>009-012>015-017-018-020-022>027-032>034-103-104-  
116-203-204-216.  
OH...HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR OHZ001-002-004-  
005-015-016-024-025.  
MI...NONE.  
MARINE...NONE.  
 

 
 

 
 
DISCUSSION...JOHNSON  
AVIATION...ANDERSEN  
 
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