Weather Alerts For Great Lakes, IL

# HEADLINE -------------------- EXTREME HEAT WARNING REMAINS IN EFFECT UNTIL MIDNIGHT CDT THURSDAY NIGHT # DETAILS -------------------- WHAT Dangerously hot conditions with peak afternoon heat index values of 100 to 110 degrees. WHERE Northern and central Illinois and northwest Indiana. WHEN Until midnight CDT Thursday Night. IMPACTS Heat related illnesses increase significantly during extreme heat and high humidity events. ISSUED AT Wednesday, July 1, 2026 at 2:30 AM CDT ISSUED BY National Weather Service Chicago IL HEADER URGENT - WEATHER MESSAGE # PRECAUTIONARY/PREPAREDNESS ACTIONS -------------------- 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 -------------------- 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 Lombard, Aurora, Rockford, Naperville, Oregon, Portage, McHenry, Channahon, Byron, Peotone, Waukegan, Fowler, Minooka, Belvidere, Bourbonnais, Coal City, DeKalb, Marseilles, Oxford, Pontiac, Ottawa, Woodstock, Yorkville, Streator, Wilmington, Carol Stream, Crete, DeMotte, Bolingbrook, Mendota, Mundelein, Algonquin, Kankakee, Joliet, Dixon, Watseka, Hammond, Merrillville, Bradley, Elgin, Sycamore, Beecher, Morris, Gibson City, Mokena, Plainfield, La Salle, Roselawn, Gurnee, Plano, Chesterton, Gary, Kentland, Dwight, Valparaiso, Rochelle, Manhattan, Oswego, Fairbury, Gilman, Wheaton, Paxton, Morocco, Buffalo Grove, Rensselaer, Crystal Lake, and Downers Grove