662
FLUS43 KLOT 270916
HWOLOT
HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
416 AM CDT MON JUL 27 2026
ILZ003>006-008-010>013-019>021-023-032-033-039-103>108-INZ001-002-
010-011-019-280930-
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-
416 AM CDT MON JUL 27 2026 /516 AM EDT MON JUL 27 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...
ELEVATED THUNDERSTORM RISK...WITH AN ASSOCIATED:
LEVEL 3 OF 5 DAMAGING WIND RISK...LOCALLY OVER 70 MPH.
LEVEL 2 OF 5 LARGE HAIL RISK...UP TO GOLF BALL SIZE.
LEVEL 1 OF 5 TORNADO RISK.
LIMITED FLOODING RISK.
ELEVATED TO SIGNIFICANT EXCESSIVE HEAT RISK.
HIGH SWIM RISK LAKE MICHIGAN BEACHES LATE TONIGHT.
DISCUSSION...
THERE IS A CHANCE OF THUNDERSTORMS TODAY INTO THE EARLY EVENING
HOURS. IF STORM OCCUR, THEY COULD BE SEVERE, CAPABLE OF
DESTRUCTIVE WINDS LOCALLY OVER 70 MPH AND HAIL TO THE SIZE OF GOLF
BALLS. ANY STORMS THAT FORM TODAY WILL ALSO PRODUCE TORRENTIAL
RAINFALL.
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 THROUGH WEDNESDAY MORNING...
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 MONDAY MORNING, SOME OF WHICH MAY
PRODUCE LOCALLY DAMAGING WIND GUSTS AND LARGE HAIL.
AN ADDITIONAL ROUND OF THUNDERSTORMS MAY OCCUR LATE MONDAY
AFTERNOON INTO THE 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 POSSIBLE MONDAY 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>745-280930-
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-
416 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
TODAY 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.
- IZZI
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