057  
FLUS43 KLOT 170837  
HWOLOT  
 
HAZARDOUS WEATHER OUTLOOK  
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL  
337 AM CDT WED JUN 17 2026  
 
ILZ003>006-008-010>013-019>021-023-032-033-039-103>108-INZ001-002-  
010-011-019-180845-  
WINNEBAGO-BOONE-MCHENRY-LAKE IL-OGLE-LEE-DE KALB-KANE-DUPAGE-  
LA SALLE-KENDALL-GRUNDY-KANKAKEE-LIVINGSTON-IROQUOIS-FORD-  
NORTHERN COOK-CENTRAL COOK-SOUTHERN COOK-NORTHERN WILL-  
SOUTHERN WILL-EASTERN WILL-LAKE IN-PORTER-NEWTON-JASPER-BENTON-  
337 AM CDT WED JUN 17 2026 /437 AM EDT WED JUN 17 2026/  
 
THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTH CENTRAL  
ILLINOIS...NORTHEAST ILLINOIS AND NORTHWEST INDIANA.  
   
DAY ONE  
TODAY AND TONIGHT.  
 
WEATHER HAZARDS EXPECTED...  
 
SIGNIFICANT THUNDERSTORM RISK...WITH AN ASSOCIATED:  
LEVEL 4 OF 5 TORNADO RISK.  
LEVEL 3 OF 5 DAMAGING WIND RISK...UP TO 80 MPH.  
LEVEL 2 OF 5 LARGE HAIL RISK...UP TO GOLF BALL SIZE.  
SIGNIFICANT FLOODING RISK.  
HIGH SWIM RISK LAKE MICHIGAN BEACHES.  
 
DISCUSSION...  
 
SCATTERED THUNDERSTORM ARE LIKELY STARTING THIS MORNING AND  
CONTINUING AT TIMES THROUGH THE EARLY EVENING. AN ISOLATED SEVERE  
THUNDERSTORM CANNOT BE RULED OUT LATE THIS MORNING INTO THE EARLY  
AFTERNOON, ESPECIALLY SOUTH OF MENDOTA TO PAXTON LINE.  
 
A MORE SUBSTANTIAL SEVERE WEATHER THREAT IS EXPECTED BETWEEN 2 PM  
AND 9 PM. SEVERE THUNDERSTORMS FROM MID AFTERNOON THROUGH EARLY  
EVENING WILL BE CAPABLE OF PRODUCING LONG TRACKED, PARTICULARLY  
DAMAGING TORNADOES, DESTRUCTIVE WINDS UP TO 80 MPH, AND HAIL UP TO  
GOLF BALL SIZE. WHILE SOME SEVERE WEATHER THREAT WILL EXIST ACROSS  
THE ENTIRE OUTLOOK AREA, THE THREAT INCREASES AS YOU HEAD  
SOUTHWARD FROM I-80.  
 
THUNDERSTORMS TODAY WILL BE CAPABLE OF PRODUCING TORRENTIAL  
RAINFALL WHICH COULD LEAD TO LOCALIZED FLASH FLOODING.  
   
DAYS TWO THROUGH SEVEN  
THURSDAY THROUGH TUESDAY.  
 
THURSDAY...  
HIGH SWIM RISK PORTER COUNTY LAKE MICHIGAN BEACHES.  
SATURDAY...  
LIMITED THUNDERSTORM RISK.  
SUNDAY...IF  
LIMITED FLOODING RISK.  
LIMITED THUNDERSTORM RISK.  
MONDAY AND TUESDAY...  
LIMITED THUNDERSTORM RISK.  
   
SPOTTER INFORMATION STATEMENT  
 
SPOTTERS WILL LIKELY BE NEEDED THIS AFTERNOON AND EVENING.  
 
GENERAL STORM MOTION OF THE DAY:  
 
MOVING TOWARD THE EAST AT 50 TO 55 MPH.  
 
 
 
LMZ740>745-180845-  
WINTHROP HARBOR TO WILMETTE HARBOR IL-  
WILMETTE HARBOR TO NORTHERLY ISLAND IL-  
NORTHERLY ISLAND TO CALUMET HARBOR IL-  
CALUMET HARBOR IL TO GARY IN-GARY TO BURNS HARBOR IN-  
BURNS HARBOR TO MICHIGAN CITY IN-  
337 AM CDT WED JUN 17 2026  
 
THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF THE ILLINOIS  
NEARSHORE WATERS OF LAKE MICHIGAN AND THE INDIANA NEARSHORE  
WATERS OF LAKE MICHIGAN.  
   
DAY ONE  
TODAY AND TONIGHT.  
 
WEATHER HAZARDS EXPECTED...  
 
HAZARDOUS CONDITIONS FOR SMALL CRAFT ARE LIKELY.  
SIGNIFICANT THUNDERSTORM RISK...WITH AN ASSOCIATED:  
THUNDERSTORM WATERSPOUT RISK  
LEVEL 3 OF 5 THUNDERSTORM WIND GUST RISK...UP TO 65 KNOTS.  
LEVEL 2 OF 5 HAIL RISK...UP TO QUARTER SIZE.  
   
DAYS TWO THROUGH SEVEN  
THURSDAY THROUGH TUESDAY.  
 
THURSDAY MORNING...  
HAZARDOUS CONDITIONS FOR SMALL CRAFT ARE LIKELY.  
SATURDAY...  
LIMITED THUNDERSTORM RISK.  
SUNDAY...  
HAZARDOUS CONDITIONS FOR SMALL CRAFT ARE LIKELY.  
LIMITED THUNDERSTORM RISK.  
MONDAY...  
HAZARDOUS CONDITIONS FOR SMALL CRAFT ARE LIKELY.  
 
 
 
- IZZI  
 
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