309  
FXUS63 KIWX 301748  
AFDIWX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE NORTHERN INDIANA  
148 PM EDT MON JUN 30 2025  
   
KEY MESSAGES
 
 
- NUMEROUS SHOWERS AND STORMS THIS AFTERNOON AND EVENING. A FEW STORMS  
COULD BE STRONG TO SEVERE WITH DAMAGING WINDS AND HEAVY  
RAINFALL.  
 
- DRY, SEASONABLE, AND LESS HUMID BY MID TO LATE IN THE WEEK.  
 
- HOT AND HUMID BY THE WEEKEND WITH CHANCES FOR RAIN/STORMS.  
 

 
   
DISCUSSION
 
 
ISSUED AT 146 PM EDT MON JUN 30 2025  
 
A COLD FRONT IS LOCATED NEAR MILWAUKEE EXTENDING SOUTHEAST  
TOWARDS KANSAS CITY, AND IT WILL SLOWLY MOVE EAST THIS AFTERNOON  
AND EVENING. AHEAD OF THE FRONT, DESTABILIZATION IS ALREADY  
OCCURRING ACROSS OUR FORECAST AREA. A GROWING CUMULUS FIELD IS  
EVIDENT ON VISIBLE SATELLITE IMAGERY; ADDITIONALLY,  
TEMPERATURES ARE ALREADY IN THE LOW TO MID 80S AND DEWPOINTS ARE  
IN THE LOW 70S. AMIDST THIS HOT AND HUMID AIRMASS, SCATTERED  
MULTICELL CLUSTERS OF SHOWERS AND STORMS ARE ONGOING EAST OF IN  
15, FUELED BY A LAKE BREEZE COMING OFF OF LAKE MICHIGAN.  
ADDITIONAL STORMS WILL BE POSSIBLE LATER THIS EVENING AFTER  
SUNSET ALONG THE COLD FRONT. MUCH LIKE YESTERDAY, IT WILL BE  
FEAST OR FAMINE FOR STORMS. SOME LOCATIONS MAY GET NOTHING WHILE  
OTHERS GET SEVERAL INCHES OF RAIN IN A SHORT AMOUNT OF TIME.  
THE STORM PREDICTION CENTER HAS MAINTAINED THE MARGINAL RISK  
(LEVEL 1 OF 5) FOR OUR ENTIRE FORECAST AREA, MEANING A FEW  
STORMS COULD BE STRONG TO SEVERE TODAY. THE SETUP FOR SEVERE  
WEATHER APPEARS FAIRLY UNIMPRESSIVE AS THERE IS AMPLE  
INSTABILITY FOR STORMS TO WORK WITH (2500-3000 J/KG SBCAPE), BUT  
NO SOURCE OF LIFT (UNTIL THE FRONT ARRIVES) AND LITTLE TO NO  
SHEAR IN PLACE AS VERTICAL WIND PROFILES ARE UNIDIRECTIONAL OUT  
OF THE WEST-SOUTHWEST. CONFIDENCE IN SEVERE WEATHER OCCURRING IS  
LOW. INVERTED V SOUNDINGS FROM THE HREF AND NAM SHOW SOME  
POSSIBILITY FOR LOCALIZED MICROBURSTS/DAMAGING WINDS SHOULD  
STRONG TO SEVERE STORMS DEVELOP. THERE IS ALSO A MARGINAL RISK  
(LEVEL 1 OF 4) FOR LOCALIZED FLASH FLOODING PER WPC. SHOULD  
STORMS GET GOING ALONG THE LAKE BREEZE AND DIVE SOUTHWARD, SOME  
BACKBUILDING WILL BE POSSIBLE WITH LOW LEVEL LOW FROM THE WEST  
PARALLEL TO THE BOUNDARY AND SLOW CORFIDI UPSHEAR WINDS.  
PRECIPITATION RATES SHOULD BE EFFICIENT TODAY GIVEN LONG, SKINNY  
CAPE PROFILES, A DEEP WARM CLOUD LAYER, AND PWATS ABOVE THE  
75TH PERCENTILE OF 1.5-1.75".  
 
JULY WILL START DRY AND SEASONABLE AS AN UPPER LEVEL RIDGE  
EXPANDS ACROSS THE CENTRAL PLAINS AND MOVES EASTWARD. TUESDAY  
THROUGH FRIDAY WILL BE MAINLY DRY AS SURFACE HIGH PRESSURE  
BUILDS ACROSS MUCH OF THE EASTERN CONUS. AS THE UPPER LEVEL  
PATTERN BECOMES MORE AMPLIFIED OVER THE MIDWEST SATURDAY AND  
SUNDAY, HOT AND HUMID CONDITIONS RETURN. HIGHS IN THE LOW 90S  
RETURN WITH HEAT INDICES IN THE MID 90S. SOME DIURNAL CHANCES  
FOR RAIN/STORMS MAY BE POSSIBLE FOR THE 4TH OF JULY WEEKEND INTO  
EARLY NEXT WEEK.  
 

 
   
AVIATION /12Z TAFS THROUGH 12Z TUESDAY/
 
 
ISSUED AT 611 AM EDT MON JUN 30 2025  
 
CLOUDINESS BEGAN TO SCATTER OUT IN THE WEST DURING THE MID MORNING  
AND THAT HAS ALLOWED FOR SOME INSTABILITY TO FORM. MODELS ARE LITTLE  
INCONSISTENT ON WHERE STORMS WILL BE DURING THE AFTERNOON AND  
EVENING HOURS, BUT STILL FEEL CONFIDENT ENOUGH TO KEEP A MENTION OF  
SHOWERS AND STORMS AT FWA THIS AFTERNOON. WE'LL THEN HAVE TO  
WATCH THE ARRIVAL OF A COLD FRONT AFTER 00Z. GIVEN HOW MUCH  
DEBRIS CLOUDS HAVE BEEN ACROSS THE AREA THIS MORNING AND HOW  
LATE IT IS AT NIGHT, WOULD EXPECT THAT THIS SHOULD JUST STAY  
SHOWERS. SOME MVFR FLIGHT CONDITIONS WILL BE POSSIBLE FROM  
THOSE SHOWERS AS THEY MOVE THROUGH. THE COLD FRONT MOVES  
THROUGH AND BRINGS A COOLER AND DRIER AIRMASS OVERNIGHT INTO  
TUESDAY, BUT AT THIS POINT THE BR/FOG CHANCE LOOKS LOW. WINDS  
ARE STILL EXPECTED TO STAY AT OR LESS THAN 10 KTS WITH WEST  
SOUTHWEST WINDS VEERING MORE NORTHWESTERLY BY THE END OF THE  
PERIOD.  
 

 
   
IWX WATCHES/WARNINGS/ADVISORIES
 
 
IN...NONE.  
OH...NONE.  
MI...NONE.  
MARINE...NONE.  
 

 
   
IWX WATCHES/WARNINGS/ADVISORIES
 
 
IN...NONE.  
OH...NONE.  
MI...NONE.  
MARINE...NONE.  
 

 
 

 
 
DISCUSSION...JOHNSON  
AVIATION...ROLLER  
 
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