108  
FLUS43 KLOT 240102 AAA  
HWOLOT  
 
HAZARDOUS WEATHER OUTLOOK...UPDATED  
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL  
802 PM CDT WED JUL 23 2025  
 
ILZ003>006-008-010>013-019>021-023-032-033-039-103>108-INZ001-002-  
010-011-019-250115-  
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-  
802 PM CDT WED JUL 23 2025 /902 PM EDT WED JUL 23 2025/  
 
THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTH CENTRAL  
ILLINOIS...NORTHEAST ILLINOIS AND NORTHWEST INDIANA.  
   
DAY ONE
 
TONIGHT.  
 
WEATHER HAZARDS EXPECTED...  
 
ELEVATED EXCESSIVE HEAT RISK.  
 
DISCUSSION...  
 
HEAT INDICES WILL REMAIN ABOVE 75 DEGREES THROUGH THE NIGHT FOR  
MUCH OF THE AREA, WITH HEAT INDICES ONLY FALLING TO AROUND 85  
DEGREES VERY LATE TONIGHT IN CHICAGO.  
   
DAYS TWO THROUGH SEVEN
 
THURSDAY THROUGH TUESDAY.  
 
THURSDAY...  
SIGNIFICANT EXCESSIVE HEAT RISK.  
ELEVATED FLOODING RISK.  
LIMITED THUNDERSTORM RISK...WITH AN ASSOCIATED:  
LEVEL 1 OF 5 SEVERE THUNDERSTORM RISK.  
FRIDAY...  
ELEVATED FLOODING RISK.  
LIMITED THUNDERSTORM RISK.  
SATURDAY...  
LIMITED THUNDERSTORM RISK.  
LIMITED FLOODING RISK.  
SUNDAY THROUGH TUESDAY...  
LIMITED EXCESSIVE HEAT RISK.  
 
DISCUSSION...  
 
PEAK AFTERNOON HEAT INDEX VALUES OF 100 TO 110 DEGREES ARE  
EXPECTED AGAIN THURSDAY AFTERNOON.  
 
THUNDERSTORMS MAY ARRIVE AS EARLY AS THURSDAY MORNING ACROSS  
NORTHWEST ILLINOIS, WITH INCREASING CHANCES DURING THE AFTERNOON  
AND EVENING ACROSS THE AREA. ANY THUNDERSTORMS THAT OCCUR WILL BE  
CAPABLE OF GUSTY TO LOCALLY DAMAGING WIND GUSTS AS WELL AS  
TORRENTIAL RAINFALL LEADING TO LOCALIZED FLASH FLOODING.  
 
PERIODIC THUNDERSTORMS FRIDAY THROUGH SATURDAY WILL BRING THE  
CHANCE FOR TORRENTIAL RAINFALL AND LOCALIZED FLOODING.  
   
SPOTTER INFORMATION STATEMENT
 
 
SPOTTER ACTIVATION WILL NOT BE NECESSARY THROUGH TONIGHT.  
 

 
 
LMZ740>745-250115-  
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-  
802 PM CDT WED JUL 23 2025  
 
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.  
 
NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.  
   
DAYS TWO THROUGH SEVEN
 
THURSDAY THROUGH TUESDAY.  
 
THURSDAY...  
LIMITED THUNDERSTORM RISK...WITH AN ASSOCIATED:  
LEVEL 1 OF 5 SEVERE THUNDERSTORM RISK.  
FRIDAY AND SATURDAY...  
LIMITED THUNDERSTORM RISK.  
 

 
 
PETR  
 
VISIT US AT WWW.WEATHER.GOV/CHICAGO  
 
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