216  
FXUS63 KIWX 171740  
AFDIWX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE NORTHERN INDIANA  
140 PM EDT THU JUL 17 2025  
   
KEY MESSAGES
 
 
- HIGHS THROUGH MONDAY WILL BE SEASONABLY WARM IN THE 80S.  
HUMIDITY LEVELS WILL VARY WITH THE NEXT 2 DAYS BEING THE MOST  
PLEASANT.  
 
- THE BEST CHANCES FOR SHOWERS AND THUNDERSTORM SHOULD REMAIN  
SOUTH OF THE AREA UNTIL SATURDAY.  
 
- HEAT AND HUMIDITY RETURN FOR THE SECOND HALF OF NEXT WEEK  
WITH HEAT INDICIES POSSIBLY REACHING 100 DEGREES OR HIGHER.  
 
- A BEACH HAZARDS STATEMENT IS IN EFFECT FOR THE BEACHES ALONG  
SOUTHEASTERN LAKE MICHIGAN INTO THIS EVENING. WAVES OF 4 TO 6  
FEET WILL CREATE DANGEROUS CURRENTS.  
 

 
   
DISCUSSION
 
 
ISSUED AT 343 AM EDT THU JUL 17 2025  
 
COLD FRONT WAS READILY APPARENT IN SFC OBS AS WELL AS RADAR,  
EXTENDING FROM COLDWATER TO PLYMOUTH. SOMEWHAT OF A DROP IN  
DEWPOINTS NOTED WITH EVEN SOME BRIEF GUSTIER WINDS (BENTON  
HARBOR GUSTED TO 45 MPH). THE FRONT WILL PROGRESS SE, BUT  
EVENTUALLY SLOW DOWN AND STALL OUT SOUTH OF US-24 AS UPPER FLOW  
FLATTENS. THETA-E GRADIENT WILL REMAIN IN THIS VICINITY DURING  
PEAK HEATING, WHICH MAY ALLOW FOR A FEW POPUP SHOWERS OR STORMS.  
SUSPECT MAIN PATH OF CONVECTION WILL REMAIN EVEN FURTHER SOUTH,  
BUT FOR NOW WILL LIMIT POPS TO SLGT CHC IN THE FAR SOUTH. LOWER  
DEWPOINTS WILL CONTINUE SOUTH WITH SOME MODELS INDICATING  
DROPPING INTO THE 50S, ESPECIALLY NORTH. REGARDLESS, EVEN A DROP  
INTO THE LOW 60S WILL BE A NICE RELIEF, ALBEIT BRIEF. THE NW  
FLOW AND ALREADY NOTED SOMEWHAT GUSTIER WINDS WILL SET THE STAGE  
FOR A HIGH SWIM RISK  
 
THETA-E GRADIENT/BAROCLINIC ZONE WILL EDGE SLOWLY BACK NORTH  
SATURDAY WITH 70 DEWPOINTS MAKING A RETURN ALONG WITH SCATTERED TO  
POSSIBLY NUMEROUS SHOWERS AND STORMS. POP UP CONVECTION COULD HAPPEN  
AT ANY POINT, BUT BEST CHANCES LIKELY TO OCCUR FROM UPSTREAM  
CONVECTION OR ITS REMNANTS MOVING EAST INTO THE REGION ALONG WITH A  
WEAK UPPER LEVEL RIPPLE DEPICTED IN THE MODELS. SWODY3 HAS  
INTRODUCED A MARGINAL RISK (1 OUT OF 5) FOR LOCATION ALONG AND SOUTH  
OF US-30. OF GREATER CONCERN COULD BE THE COPIOUS AMOUNTS OF  
MOISTURE THAT WILL LIKELY BE IN PLACE WITH RISK OF ONE OF MORE  
ROUNDS OF SHOWERS/STORMS THAT COULD BRING AN INCREASED FLOODING  
RISK.  
 
UPPER LEVEL RIDGING WILL SLOWLY INCREASE INTO NEXT WEEK WITH THE 594  
DM UPPER LEVEL HIGH EDGING SLOWLY NORTH AND WEST AND STRENGTHEN  
FURTHER. THIS WILL LIKELY RESULT IN ANY CONVECTIVE CHANCES REMAINING  
NORTH OF THE AREA AS 700 MB CLIMB ABOVE 10 C, ESPECIALLY CAPPING THE  
ENTIRE AREA AND ALLOWING THE REGION TO BAKE AS HIGHS MAKE A RUN BACK  
INTO THE LOWER 90S AND DEWPOINTS IN THE 70S. HEAT INDICES WEDNESDAY  
AND THURSDAY WILL LIKELY TOP 100 DEGREES WITH LIMITED OVERNIGHT  
RELIEF. IN ADDITION, "CORN SWEAT" WILL BE IN FULL SWING, POTENTIALLY  
ADDING TO DEWPOINTS LOCALLY. WILL NEED TO MONITOR THIS PERIOD AS  
MODEL SIGNALS SEEM TO BE FAIRLY CONSISTENT.  
 

 
   
AVIATION /18Z TAFS THROUGH 18Z FRIDAY/
 
 
ISSUED AT 140 PM EDT THU JUL 17 2025  
 
A DRIER AIRMASS HAS FOLLOWED THE FRONT THAT MOVED THROUGH THE  
AREA EARLIER TODAY. CEILINGS HAVE BEEN IMPROVING AT KFWA SINCE  
SUNRISE TODAY WHILE KSBN REMAINS MVFR. EXPECT KSBN TO REMAIN  
MVFR OVERNIGHT BEFORE BECOMING SCTD AROUND 12Z AND KFWA  
PRIMARILY VFR. WINDS WILL REMAIN NORTHWEST OVERNIGHT BEFORE  
TURNING MORE EAST SOUTHEAST FRIDAY MORNING AS SURFACE HIGH  
PRESSURE DRIFTS EAST ACROSS THE GREAT LAKES.  
 

 
   
IWX WATCHES/WARNINGS/ADVISORIES
 
 
IN...BEACH HAZARDS STATEMENT THROUGH LATE TONIGHT FOR INZ103.  
OH...NONE.  
MI...BEACH HAZARDS STATEMENT THROUGH LATE TONIGHT FOR MIZ177-277.  
MARINE...SMALL CRAFT ADVISORY UNTIL 2 AM EDT FRIDAY FOR LMZ043-046.  
 

 
 

 
 
DISCUSSION...FISHER  
AVIATION...MF  
 
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