405  
FXUS63 KIWX 190526  
AFDIWX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE NORTHERN INDIANA  
126 AM EDT SUN JUL 19 2026  
   
KEY MESSAGES  
 
- SMOKE FROM CANADIAN WILDFIRES WILL CONTINUE TO BRING PERIODS  
OF POOR AIR QUALITY AND REDUCED VISIBILITY THROUGH AT LEAST  
MONDAY.  
 
- HIGH SWIM RISK CONDITIONS ARE EXPECTED ALONG LAKE MI BEACHES  
IN BERRIEN COUNTY, MI AND LA PORTE COUNTY, IN THIS EVENING  
INTO LATE TONIGHT. DANGEROUS WAVES AND CURRENTS ARE EXPECTED.  
 
- ADDITIONAL CHANCES FOR SHOWERS AND THUNDERSTORMS RETURN MONDAY  
NIGHT INTO TUESDAY.  
 
 
   
DISCUSSION  
 
ISSUED AT 1241 PM EDT SAT JUL 18 2026  
 
MAIN FOCUS OF FORECAST REMAINS ON ARRIVAL OF A COLD FRONT, SET TO  
BRING A ROUND OF STRONG TO SEVERE STORMS THIS AFTERNOON AND EARLY  
EVENING. IN THE WAKE OF THE FRONT, NORTHERLY WINDS WHICH WILL BRING  
COOLER AND LESS HUMID AIR AS WELL A HIGH SWIM RISK FOR THE SE LAKE  
MICHIGAN BEACHES.  
 
INITIATION HAS OCCURRED A FEW HOURS AHEAD OF SCHEDULE WITH A BROKEN  
LINE OF NON-SEVERE SHOWERS AND STORMS FROM CASS COUNTY, MI WEST TO  
CHICAGO. SPC RECENTLY ISSUED A MESOSCALE DISCUSSION HIGHLIGHTING  
THE CONCERNS AND TRENDS FOR THE NEXT SEVERAL HOURS. TO SUM IT  
UP, SUFFICIENT INSTABILITY (OVER 2000 J/KG OF SBCAPE AND A  
NARROW BAND OF AROUND 1000 J/KG OF DCAPE) IS ALREADY IN PLACE TO  
ALLOW CONTINUED ORGANIZATION OVER THE NEXT SEVERAL HOURS AS  
THEY MOVE SSE WITH PRIMARILY A DAMAGING WIND THREAT WITH THE  
STRONGER STORMS. SUFFICIENT LOW AND MID LEVEL LAPSE RATES WILL  
ALLOW FOR HAIL PRODUCTION, BUT FREEZING LEVELS AOA 15,000 FT MAY  
LEAD TO INCREASED WET MICROBURST POTENTIAL WITH EMBEDDED  
SMALLER HAIL. MOVEMENT WILL BE SOMEWHAT FASTER THAN YESTERDAY,  
BUT PWATS ABOVE 1.75" WILL ALLOW FOR SOME ISOLATED HYDRO  
CONCERNS, ESPECIALLY IN ISOLATED AREAS THAT RECEIVED 2 TO 7  
INCHES OF RAIN OVER THE PAST 24 HOURS. MAINTAINING A PERIOD OF  
HIGH LIKELY POPS ALONG AND AHEAD OF THE FRONT.  
 
THE FRONT WILL CLEAR THE AREA THIS EVENING WITH INCREASING NW WINDS  
TO BRING A PEAK TO DANGEROUS SWIM CONDITIONS FOR ALL BEACHES ALONG  
SE LAKE MICHIGAN. BEACH HAZARD STATEMENTS REMAIN IN EFFECT INTO  
SUNDAY. WINDS WILL SHIFT MORE NE WITH TIME AND SLOWLY REDUCE THE  
RISK SUNDAY NIGHT.  
 
COOLER AND SLIGHTLY LESS HUMID CONDITIONS ARRIVE BEHIND THE FRONT AS  
THE HEAT DOME SHIFTS WEST AND WE END UP IN A NW FLOW ALOFT WHICH  
PERSISTS THROUGH THE REMAINDER OF THE PERIOD. AS IS OFTEN THE CASE  
WITH THESE NW FLOW SETUPS, ONE OR MORE CONVECTIVE COMPLEXES ARE  
LIKELY TO DEVELOP UPSTREAM AND MAY MOVE ACROSS PORTIONS OF THE  
REGION. THE MAIN POTENTIAL RIGHT NOW LOOK TO RESIDE WITH A STRONGER  
TROUGH ARRIVING LATER MONDAY INTO TUESDAY WHICH WILL LIKELY BRING  
SOME SHOWERS AND STORMS AND MAYBE A RISK OF SEVERE WEATHER,  
DEPENDING ON THE TIMING OF THE FEATURE.  
 
 
   
AVIATION /06Z TAFS THROUGH 06Z MONDAY/  
 
ISSUED AT 122 AM EDT SUN JUL 19 2026  
 
MVFR VSBYS THROUGH ABOUT 08Z-10Z SUN DUE TO SMOKE AND HAZE.  
OTHERWISE, VFR CONDITIONS EXPECTED WITH LIGHT VARIABLE TO NORTHERLY  
WINDS AROUND 5KTS THROUGH THE TAF PERIOD.  
 
 
   
IWX WATCHES/WARNINGS/ADVISORIES  
 
IN...AIR QUALITY ALERT UNTIL MIDNIGHT EDT /11 PM CDT/ TONIGHT FOR  
INZ005>009-012>015-017-018-020-022>027-032>034-103-104-  
116-203-204-216.  
BEACH HAZARDS STATEMENT UNTIL 4 AM CDT EARLY THIS MORNING FOR  
INZ103.  
OH...NONE.  
MI...AIR QUALITY ALERT UNTIL MIDNIGHT EDT TONIGHT FOR MIZ078>081-  
177-277.  
BEACH HAZARDS STATEMENT UNTIL 5 AM EDT EARLY THIS MORNING FOR  
MIZ177-277.  
MARINE...SMALL CRAFT ADVISORY UNTIL 5 AM EDT EARLY THIS MORNING FOR  
LMZ043-046.  
 
 
 
 
 
DISCUSSION...FISHER  
AVIATION...ANDERSEN  
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