# HEADLINE
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EXTREME HEAT WARNING IN EFFECT UNTIL MIDNIGHT CDT /1 AM EDT/ THURSDAY NIGHT
# DETAILS
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WHAT
Dangerously hot conditions with heat index values around 105 expected each afternoon.
WHERE
Portions of central, east central, north central, and northeast Illinois and northwest Indiana.
WHEN
Until midnight CDT /1 AM EDT/ Thursday Night.
IMPACTS
Heat related illnesses increase significantly during extreme heat and high humidity events.
ADDITIONAL DETAILS
Dangerous heat is now expected to persist through Thursday. Thunderstorms may begin to bring some relief from the heat for portions of northern Illinois by Thursday afternoon or evening.
ISSUED AT
Tuesday, June 30, 2026 at 1:51 AM CDT
ISSUED BY
National Weather Service Chicago IL
HEADER
URGENT - WEATHER MESSAGE
# PRECAUTIONARY/PREPAREDNESS ACTIONS
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Drink plenty of fluids, stay in an air-conditioned room, stay out of the sun, and check up on relatives and neighbors.
Do not leave young children and pets in unattended vehicles. Car interiors will reach lethal temperatures in a matter of minutes.
# AREAS AFFECTED
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Benton, Boone, De Kalb, DuPage, Eastern Will, Ford, Grundy, Iroquois, Jasper, Kane, Kankakee, Kendall, La Salle, Lake IL, Lake IN, Lee, Livingston, McHenry, Newton, Northern Will, Ogle, Porter, Southern Will, Winnebago
Including the cities of Rockford, Streator, Mendota, Yorkville, Channahon, Wheaton, Portage, Algonquin, Minooka, Bourbonnais, DeKalb, Dixon, Oregon, Mundelein, Chesterton, Crystal Lake, Sycamore, Belvidere, Ottawa, Marseilles, Wilmington, Morocco, Fairbury, Rensselaer, Naperville, DeMotte, Crete, Roselawn, Gibson City, Woodstock, Dwight, Lombard, Hammond, La Salle, Pontiac, Plano, Fowler, Waukegan, Elgin, Bolingbrook, Byron, Plainfield, Gary, Kentland, Mokena, Kankakee, Coal City, Gilman, Paxton, Beecher, Rochelle, Bradley, Joliet, Peotone, McHenry, Oswego, Morris, Valparaiso, Watseka, Oxford, Manhattan, Merrillville, Downers Grove, Carol Stream, Buffalo Grove, Gurnee, and Aurora
