075  
FXUS63 KIWX 020641  
AFDIWX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE NORTHERN INDIANA  
241 AM EDT TUE SEP 2 2025  
   
KEY MESSAGES
 
 
- DRY THROUGH WEDNESDAY AFTERNOON. HIGHS NEAR 80 TODAY AND WEDNESDAY.  
 
- 60-80% CHANCES FOR RAIN (AND MAYBE A FEW STORMS) WEDNESDAY EVENING  
THROUGH EARLY THURSDAY MORNING.  
 
- TURNING SHARPLY COOLER THURSDAY WITH HIGHS ONLY IN THE 60S.  
 
- BRIEFLY WARMER ON FRIDAY WITH 20-30% CHANCES FOR RAIN, THEN COOLER  
AND DRY FOR THE UPCOMING WEEKEND.  
 
- THERE IS A HIGH SWIM RISK FOR SOUTHERN LAKE MICHIGAN BEACHES  
IN LA PORTE, IN AND BERRIEN COUNTY, MI ON THURSDAY. HAZARDOUS  
SWIMMING CONDITIONS PERSIST INTO FRIDAY AND SATURDAY AS WELL,  
WITH A HIGH SWIM RISK FOR BERRIEN COUNTY, MI AND A MODERATE  
SWIM RISK FOR LA PORTE COUNTY, IN.  
 

 
   
DISCUSSION
 
 
ISSUED AT 238 AM EDT TUE SEP 2 2025  
 
ONE MORE COMPLETELY DRY DAY TODAY BEFORE BIG CHANGES ARE IN STORE BY  
MIDWEEK. EXPECT COMFORTABLE HUMIDITY LEVELS, MOSTLY SUNNY SKIES, AND  
HIGH TEMPERATURES NEAR 80 DEGREES TODAY. THE AREA OF HIGH PRESSURE  
THAT HAS BEEN OVER THE REGION OVER THE PAST SEVERAL DAYS HAS STARTED  
TO MOVE EASTWARD, SETTING THE STAGE FOR A POTENT UPPER LEVEL TROUGH  
AND ATTENDANT STRONG SURFACE COLD FRONT TO PIVOT THROUGH THE MIDWEST  
AND GREAT LAKES LATE WEDNESDAY THROUGH EARLY THURSDAY. THE MORNING  
AND AFTERNOON HOURS WILL BE DRY TOMORROW, BUT THE AFOREMENTIONED  
COLD FRONT WILL BRING 60-80% CHANCES FOR RAIN STARTING LATE IN  
THE AFTERNOON IN OUR FAR NORTHWEST. A FEW EMBEDDED  
THUNDERSTORMS WILL BE POSSIBLE AS WELL GIVEN ~500 J/KG OF  
SURFACE INSTABILITY. THE COLD FRONT WILL MOVE FROM THE NORTHWEST  
TO SOUTHEAST, BRINGING INCREASING RAIN CHANCES TO THE AREA  
WEDNESDAY EVENING AND INTO THE OVERNIGHT HOURS. RAIN WILL COME  
TO AN END AROUND DAYBREAK THURSDAY AS THE COLD FRONT IS EXPECTED  
TO BE WELL INTO CENTRAL OHIO AND CENTRAL INDIANA BY THEN. PWAT  
VALUES WILL BE AROUND THE 75TH PERCENTILE OF NORMAL AND WITH A  
STRONG SOURCE OF LIFT VIA THE COLD FRONT, A MUCH NEEDED SOAKING  
RAINFALL IS POSSIBLE FOR MUCH OF THE AREA. AT THIS TIME, 0.50"  
IS LIKELY AREA-WIDE. FORECAST SOUNDINGS DEPICT TALL, SKINNY CAPE  
PROFILES AND A DEEP WARM CLOUD LAYER, SO IF RAINFALL IS  
EFFICIENT ENOUGH, SOME LOCATIONS COULD BE LOOKING AT 0.75" TO 1"  
OF RAIN. SEVERE WEATHER IS NOT EXPECTED, HOWEVER, GUSTY WINDS  
WILL LIKELY ACCOMPANY THE RAIN AND POTENTIAL FEW THUNDERSTORMS.  
 
STRONG CAA AND NORTHWEST FLOW ON THURSDAY WILL USHER IN MUCH COOLER  
TEMPERATURES POST-FRONT. A COOL CANADIAN AIRMASS WILL OVERSPREAD  
MUCH OF THE MIDWEST AND GREAT LAKES REGIONS WITH COOLER THAN NORMAL  
TEMPERATURES. HIGHS THURSDAY WILL BE ONLY IN THE MID TO UPPER 60S  
AREA-WIDE, WHICH IS ABOUT 10 DEGREES BELOW NORMAL FOR THIS TIME OF  
YEAR. OVERNIGHT LOWS THURSDAY INTO FRIDAY WILL FALL WELL INTO THE  
40S WITH SOME AREAS APPROACHING RECORD COLD TEMPERATURES. ENJOY THE  
EARLY FALL PREVIEW!  
 
WINDS SHIFT FROM THE NORTHWEST TO SOUTHWEST LATE THURSDAY INTO THE  
DAY ON FRIDAY, WITH BREEZY CONDITIONS AND WAA BOOSTING TEMPERATURES  
UP INTO THE UPPER 60S TO LOW 70S ON FRIDAY (A FEW DEGREES WARMER  
THAN PREVIOUSLY FORECAST) A SECONDARY COLD FRONT WILL SWEEP THROUGH  
ON FRIDAY WITH 20-30% CHANCES FOR RAIN. THIS SECOND COLD FRONT WILL  
REINSTATE NORTHWEST FLOW AND REINFORCE COOLER THAN NORMAL  
TEMPERATURES FOR THE WEEKEND. HAVE KEPT WITH THE NBM FOR NOW IN THE  
LONG RANGE, WHICH HAS HIGHS IN THE LOW 70S AREA-WIDE OVER THE  
WEEKEND. MID TO LONG RANGE MODEL GUIDANCE HAS CAUGHT ONTO THIS  
SECONDARY COLD FRONT AND HAS TRENDED TOWARDS COOLER THAN NORMAL  
TEMPERATURES PERSISTING INTO EARLY NEXT WEEK. TEMPERATURES WILL  
GRADUALLY MODERATE BACK TOWARDS SEASONABLE LEVELS NEXT WEEK.  
 
ADDITIONALLY, BREEZY NORTHWEST WINDS ON THURSDAY WILL GENERATE HIGH  
WAVES OVER LAKE MICHIGAN. WAVES WILL START TO INCREASE AFTER SUNSET  
ON WEDNESDAY; THE STRONG COLD FRONT MAY CREATE  
SEICHE/METEOTSUNAMI ACTIVITY ACROSS SOUTHERN LAKE MICHIGAN THAT  
COULD INTENSIFY WAVE DEVELOPMENT. THERE IS A HIGH SWIM RISK FOR  
BOTH BERRIEN COUNTY, MI AND LA PORTE COUNTY, IN BEACHES ON  
THURSDAY WITH WAVES EXPECTED IN THE 4 TO 8 FEET RANGE. STAY OUT  
OF THE WATER AND STAY OFF OF PIERS/BREAKWALLS! STRONG RIP AND  
STRUCTURAL CURRENTS ARE EXPECTED IN ADDITION TO THE HIGH WAVE  
ACTION. HAZARDOUS SWIMMING CONDITIONS PERSIST INTO FRIDAY AND  
SATURDAY AS WELL, WITH A HIGH SWIM RISK FOR BERRIEN COUNTY, MI  
AND A MODERATE SWIM RISK FOR LA PORTE COUNTY, IN.  
 

 
   
AVIATION /06Z TAFS THROUGH 06Z WEDNESDAY/
 
 
ISSUED AT 1249 AM EDT TUE SEP 2 2025  
 
ONE MORE DAY OF MOSTLY SUNNY SKIES AND LIGHT WINDS IS EXPECTED  
TODAY AS STRONG RIDGE OF HIGH PRESSURE REMAINS ANCHORED OVER THE  
REGION. A FEW 4-5 KFT DIURNAL CU ARE POSSIBLE BUT VFR IS  
ASSURED THROUGH THE PERIOD.  
 

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

 
 

 
 
DISCUSSION...JOHNSON  
AVIATION...AGD  
 
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