754  
FLUS43 KLOT 212027  
HWOLOT  
 
HAZARDOUS WEATHER OUTLOOK  
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL  
327 PM CDT FRI AUG 21 2026  
 
ILZ003>006-008-010>013-019>021-023-032-033-039-103>108-INZ001-002-  
010-011-019-222030-  
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-  
327 PM CDT FRI AUG 21 2026 /427 PM EDT FRI AUG 21 2026/  
 
THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTH CENTRAL  
ILLINOIS...NORTHEAST ILLINOIS AND NORTHWEST INDIANA.  
   
DAY ONE
 
TONIGHT.  
 
WEATHER HAZARDS EXPECTED...  
 
ELEVATED THUNDERSTORM RISK...WITH AN ASSOCIATED:  
LEVEL 1 OF 5 TORNADO RISK.  
LEVEL 2 OF 5 DAMAGING WIND RISK...UP TO 60 MPH.  
LEVEL 2 OF 5 LARGE HAIL RISK...UP TO GOLF BALL SIZE.  
LIMITED FLOODING RISK.  
 
DISCUSSION...  
 
SCATTERED THUNDERSTORMS ARE EXPECTED THROUGH THIS EVENING. THE  
PRIMARY THREATS WILL BE LARGE HAIL AND DAMAGING WINDS. AN  
ISOLATED TORNADO WILL ALSO BE POSSIBLE.  
   
DAYS TWO THROUGH SEVEN
 
SATURDAY THROUGH THURSDAY.  
 
SATURDAY...  
LIMITED THUNDERSTORM RISK.  
HIGH SWIM RISK LAKE MICHIGAN BEACHES IN PORTER COUNTY.  
SUNDAY...  
HIGH SWIM RISK LAKE MICHIGAN BEACHES.  
TUESDAY THROUGH THURSDAY...  
LIMITED THUNDERSTORM RISK.  
 
DISCUSSION...  
 
ISOLATED THUNDERSTORMS ARE POSSIBLE SATURDAY. SEVERE WEATHER IS  
NOT EXPECTED.  
 
HIGH WAVES WILL CREATE DANGEROUS SWIMMING CONDITIONS AT LAKE  
MICHIGAN BEACHES IN PORTER COUNTY INDIANA SATURDAY AND POSSIBLY  
AT ALL LAKE MICHIGAN BEACHES SUNDAY.  
   
SPOTTER INFORMATION STATEMENT
 
 
SPOTTERS MAY BE NEEDED THROUGH THIS EVENING.  
 
GENERAL STORM MOTION OF THE DAY:  
 
MOVING TOWARD THE SOUTHEAST AT 20 TO 30 MPH.  
 

 
 
LMZ740>745-222030-  
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-  
327 PM CDT FRI AUG 21 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
 
TONIGHT.  
 
WEATHER HAZARDS EXPECTED...  
 
ELEVATED THUNDERSTORM RISK...WITH AN ASSOCIATED:  
LEVEL 2 OF 5 THUNDERSTORM WIND GUST RISK...UP TO 50 KNOTS.  
LEVEL 2 OF 5 HAIL RISK...UP TO HALF DOLLAR SIZE.  
   
DAYS TWO THROUGH SEVEN
 
SATURDAY THROUGH THURSDAY.  
 
SATURDAY...  
LIMITED THUNDERSTORM RISK.  
SUNDAY...  
HAZARDOUS CONDITIONS FOR SMALL CRAFT ARE LIKELY.  
TUESDAY THROUGH THURSDAY...  
LIMITED THUNDERSTORM RISK.  
 

 
 
VISIT US AT WWW.WEATHER.GOV/CHICAGO  
 
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