530  
FXUS63 KIWX 180957  
AFDIWX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE NORTHERN INDIANA  
557 AM EDT SAT JUL 18 2026  
   
KEY MESSAGES  
 
- SMOKE FROM CANADIAN WILDFIRES WILL CONTINUE TO BRING PERIODS  
OF POOR AIR QUALITY AND REDUCED VISIBILITY THROUGH AT LEAST  
MONDAY.  
 
- SLIGHT CHANCE FOR SEVERE STORMS THIS AFTERNOON AND INTO THE  
EVENING. DAMAGING WINDS AND HEAVY DOWNPOURS WILL BE THE MAIN  
THREATS.  
 
- HIGH SWIM RISK CONDITIONS ARE EXPECTED TODAY ALONG LAKE MI  
BEACHES IN BERRIEN COUNTY, MI AND LA PORTE COUNTY, IN BY LATE  
AFTERNOON AND EVENING. MODERATE SWIM RISK CONDITIONS ARE  
EXPECTED EARLIER IN THE DAY. DANGEROUS WAVES AND CURRENTS ARE  
EXPECTED.  
 
 
   
DISCUSSION  
 
ISSUED AT 515 AM EDT SAT JUL 18 2026  
 
A SHORTWAVE TROUGH MOVING THROUGH THE CYCLONIC FLOW ON THE  
EASTERN SIDE OF HIGH AMPLITUDE RIDGING OVER THE PLAINS AND INTO  
CENTRAL CANADA. A COLD FRONT ASSOCIATED WITH THIS SHORTWAVE WILL  
BEGIN TO PUSH SOUTH INTO OUR AREA AROUND MIDDAY. SBCAPE VALUES  
OF 2500-3000 J/KG WILL BE AVAILABLE ALONG WITH BULK SHEAR  
VALUES OF 25 TO AROUND 50 KTS. SURFACE DEW POINTS IN THE MID 70S  
WILL PROVIDE AMPLE MOISTURE AND PW VALUES ARE AROUND THE 2 INCH  
MARK TODAY. STORMS TODAY SHOULD HAVE A FAIRLY PROGRESSIVE SPEED  
SO WILL HELP KEEP THE FLOODING RISK A BIT LOWER THAN THE LAST  
COUPLE OF DAYS WHEN THE STEERING FLOW WAS MUCH SLOWER. HELICITY  
VALUES ARE FORECAST TO BE ONLY AROUND 50 M2/S2 WHICH WILL KEEP  
THE RISK OF TORNADIC ACTIVITY LOW. HOWEVER, WITH ANY BOUNDARY IN  
CLOSE PROXIMITY TO STORMS THERE COULD BE AN ISOLATED BRIEF SPIN  
UP OR TWO. LAPSE RATES OF 6.5-7.0 DEG/KM WILL HELP TO ALLOW FOR  
SOME HAIL PRODUCTION HOWEVER NOT IDEAL FOR LARGE HAIL ESPECIALLY  
WITH THE VERY HUMID AND WARM LOWER LEVELS BUT THE MELTING OF  
HAIL COUPLED WITH THE HEAVIER DOWNPOUR POTENTIAL WILL MAKE  
OUTFLOW GUSTS THE BIGGEST THREAT WITH THE STORMS TODAY. SPC DID  
ADD A FAIRLY SMALL SECTION OF ENHANCED TO OUR FAR EASTERN  
PORTIONS OF THE CWA IN HENRY AND PUTNAM COUNTIES OF OHIO WITH  
THE BETTER DYNAMICS FURTHER EAST OF OUR AREA. HOWEVER, THE  
MAJORITY OF THE AREA IS CURRENTLY UNDER A SLIGHT RISK TODAY.  
 
IN THE WAKE OF THE COLD FRONT AS IT PUSHES SOUTHWARD A MORE  
NORTHERLY FLOW WILL ARRIVE AND THIS WILL MAKE FOR HAZARDOUS  
BEACH CONDITIONS OVER THE SOUTHEASTERN LAKE MICHIGAN AND WAVE  
HEIGHTS FROM 3 TO 6 FEET ON THE BIG LAKE. A BEACH HAZARDS  
STATEMENT HAS BEEN ISSUED TO ADDRESS THIS THREAT AS WELL AS A  
SMALL CRAFT ADVISORY. DRIER AIRMASS WILL ALSO ACCOMPANY THE  
FRONTAL PASSAGE.  
 
SUNDAY WILL BE A BIT COOLER AND DRIER WITH A MORE NORTHWESTERLY  
FLOW ALOFT AND HIGH TEMPERATURES WILL BE MAINLY IN THE LOW TO  
MID 80S AND DEW POINTS ONLY IN THE 60S. WE WILL ALSO SEE A SHORT  
BREAK IN PRECIPITATION CHANCES ON SUNDAY INTO MONDAY BEFORE  
ANOTHER TROUGH PUSHES INTO THE LOWER GREAT LAKES REGION ON  
MONDAY EVENING. THIS WILL ALSO BRING ANOTHER CHANCE OF SHOWERS  
AND THUNDERSTORMS TO THE AREA. A FEW OF THE STORMS MAY BECOME  
STRONG TO SEVERE SO WILL NEED TO WATCH THIS IN THE COMING DAYS.  
 
A NORTHWESTERLY FLOW ALOFT SETS UP AGAIN OVER THE REGION BY  
TUESDAY AND REMAINS THROUGH THE REST OF NEXT WEEK AND THIS WILL  
HELP TO KEEP TEMPERATURES SLIGHTLY COOLER TO NEAR NORMAL VALUES.  
 
 
   
AVIATION /06Z TAFS THROUGH 06Z SUNDAY/  
 
ISSUED AT 1248 AM EDT SAT JUL 18 2026  
 
MOSTLY VFR CONDITIONS EXPECTED THROUGH AT LEAST 15Z SAT. A COLD  
FRONT WILL PUSH SOUTHWARD AFTER THIS TIME AND BRING SCATTERED  
THUNDERSTORMS INTO THE AREA AS IT PUSHES SOUTH THROUGH THE  
EVENING PERIOD. MVFR TO IFR VSBYS IN ANY THUNDERSTORM DOWNPOURS  
ALONG WITH MVFR CIGS. MAINLY VFR CONDITIONS SHOULD RETURN AFTER  
THE COLD FRONT PUSHES SOUTH THROUGH THE AREA AFTER 21Z SAT FOR  
KSBN AND AFTER 01Z SUN FOR KFWA. GUSTY SOUTHWESTERLY WINDS EARLY  
FOR BOTH TAF SITES BEFORE A SHIFT TO MORE NORTHWESTERLY POST  
FRONTAL. GUSTS UP TO 25 KTS POSSIBLE ESPECIALLY WITHIN OR NEAR  
THUNDERSTORMS.  
 
 
   
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 FROM THIS EVENING THROUGH LATE TONIGHT  
FOR INZ103.  
OH...NONE.  
MI...AIR QUALITY ALERT UNTIL MIDNIGHT EDT TONIGHT FOR MIZ078>081-  
177-277.  
BEACH HAZARDS STATEMENT FROM 5 PM EDT THIS AFTERNOON THROUGH  
LATE TONIGHT FOR MIZ177-277.  
MARINE...SMALL CRAFT ADVISORY FROM 2 PM THIS AFTERNOON TO 5 AM EDT  
SUNDAY FOR LMZ043.  
SMALL CRAFT ADVISORY FROM 5 PM THIS AFTERNOON TO 5 AM EDT  
SUNDAY FOR LMZ046.  
 
 
 
 
 
DISCUSSION...ANDERSEN  
AVIATION...  
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