291
FLUS43 KLOT 271608
HWOLOT
HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
1108 AM CDT MON JUL 27 2026
ILZ003>006-008-010>013-019>021-023-032-033-039-103>108-INZ001-002-
010-011-019-281615-
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-
1108 AM CDT MON JUL 27 2026 /1208 PM EDT MON JUL 27 2026/
THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTH CENTRAL
ILLINOIS...NORTHEAST ILLINOIS AND NORTHWEST INDIANA.
DAY ONE
THIS AFTERNOON AND TONIGHT.
WEATHER HAZARDS EXPECTED...
ELEVATED THUNDERSTORM RISK...WITH AN ASSOCIATED:
LEVEL 1 OF 5 TORNADO RISK.
LEVEL 3 OF 5 DAMAGING WIND RISK...LOCALLY UP TO 70 MPH.
LEVEL 2 OF 5 LARGE HAIL RISK...UP TO GOLF BALL SIZE.
LIMITED FLOODING RISK.
SIGNIFICANT EXCESSIVE HEAT RISK.
HIGH SWIM RISK LAKE MICHIGAN BEACHES LATE TONIGHT.
DISCUSSION...
PERIODS OF THUNDERSTORMS WILL BE POSSIBLE THIS AFTERNOON AND
EVENING. IF STORMS OCCUR, THEY MAY BECOME SEVERE WITH LARGE HAIL
AND DAMAGING WINDS.
OUTSIDE OF ANY STORMS, STIFLING HUMIDITY WILL COMBINE WITH
HOT TEMPERATURES TO PRODUCE DANGEROUS HEAT INDICES BETWEEN 100
AND 115 DEGREES. THE HIGHEST HEAT INDICES ARE EXPECTED NEAR THE
I-39 CORRIDOR.
LARGE WAVES AND DANGEROUS CURRENTS ARE EXPECTED AT UNPROTECTED
LAKE MICHIGAN BEACHES LATE TONIGHT.
DAYS TWO THROUGH SEVEN
TUESDAY THROUGH SUNDAY.
TUESDAY...
HIGH SWIM RISK LAKE MICHIGAN BEACHES.
THURSDAY...
LIMITED THUNDERSTORM RISK.
FRIDAY...
ELEVATED FLOODING RISK.
LIMITED THUNDERSTORM RISK.
SATURDAY AND SUNDAY...
LIMITED THUNDERSTORM RISK.
DISCUSSION...
THUNDERSTORMS ARE POSSIBLE LATE THIS MORNING, SOME OF WHICH MAY
PRODUCE LOCALLY DAMAGING WIND GUSTS AND LARGE HAIL.
ADDITIONAL THUNDERSTORMS MAY OCCUR LATE THIS AFTERNOON INTO THIS
EVENING. ANY STORMS THAT DO DEVELOP WOULD LIKELY BECOME SEVERE AND
BE CAPABLE OF PRODUCING DAMAGING WINDS AND LARGE HAIL.
IN AREAS NOT AFFECTED BY STORMS OR CLOUDINESS FROM STORMS, PEAK
HEAT INDICES OF 100 TO 110 DEGREES ARE EXPECTED THIS AFTERNOON.
SPOTTER INFORMATION STATEMENT
SPOTTERS MAY BE NEEDED TODAY INTO THIS EVENING.
GENERAL STORM MOTION OF THE DAY:
MOVING TOWARD THE SOUTHEAST AT 30 MPH.
LMZ740>745-281615-
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-
1108 AM CDT MON JUL 27 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
THIS AFTERNOON AND TONIGHT.
WEATHER HAZARDS EXPECTED...
HAZARDOUS CONDITIONS FOR SMALL CRAFT.
ELEVATED 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 GOLF BALL SIZE.
DAYS TWO THROUGH SEVEN
TUESDAY THROUGH SUNDAY.
TUESDAY AND WEDNESDAY...
HAZARDOUS CONDITIONS FOR SMALL CRAFT ARE LIKELY.
THURSDAY THROUGH SATURDAY...
LIMITED THUNDERSTORM RISK.
DOOM
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