991
FLUS43 KLOT 200844
HWOLOT
HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
344 AM CDT SUN SEP 20 2026
ILZ003>006-008-010>013-019>021-023-032-033-039-103>108-INZ001-002-
010-011-019-210845-
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-
344 AM CDT SUN SEP 20 2026 /444 AM EDT SUN SEP 20 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...
LIMITED THUNDERSTORM RISK.
ELEVATED FLOODING RISK.
HIGH SWIM RISK LAKE MICHIGAN BEACHES.
DISCUSSION...
SHOWERS AND SCATTERED THUNDERSTORMS WILL CONTINUE THROUGH
MIDDAY TODAY. TORRENTIAL RAIN MAY LEAD TO LOCALIZED FLASH
FLOODING THIS MORNING.
HIGH WAVES WILL LEAD TO DANGEROUS SWIMMING CONDITIONS AT LAKE
MICHIGAN BEACHES.
DAYS TWO THROUGH SEVEN
MONDAY THROUGH SATURDAY.
MONDAY THROUGH WEDNESDAY...
HIGH SWIM RISK LAKE MICHIGAN BEACHES.
DISCUSSION...
RIVER RISES ARE LIKELY, PARTICULARLY ON PARTS OF THE ROCK, FOX,
DUPAGE, DES PLAINES, AND ILLINOIS RIVERS.
PERSISTENT NORTHEAST WINDS WILL MAINTAIN HIGH WAVES AND
DANGEROUS SWIMMING CONDITIONS AT LAKE MICHIGAN BEACHES THROUGH
THE MIDDLE OF THIS WEEK.
SPOTTER INFORMATION STATEMENT
SPOTTER ACTIVATION WILL NOT BE NECESSARY THROUGH TONIGHT.
GENERAL STORM MOTION OF THE DAY:
MOVING TOWARD THE EAST AT 25 TO 35 MPH.
LMZ740>745-210845-
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-
344 AM CDT SUN SEP 20 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.
LIMITED THUNDERSTORM RISK.
DAYS TWO THROUGH SEVEN
MONDAY THROUGH SATURDAY.
MONDAY THROUGH WEDNESDAY...
HAZARDOUS CONDITIONS FOR SMALL CRAFT ARE LIKELY.
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