Heat Advisory

Locations Affected

Aurora, IL ∙ Rockford, IL ∙ Elgin, IL ∙ Gary, IN ∙ Hammond, IN ∙ North Park, IL ∙ Ottawa, IL ∙ Harvard, IL ∙ Bristol, IL ∙ Saint Charles, IL

Full Alert Message

URGENT - WEATHER MESSAGE National Weather Service Chicago IL 548 AM CDT Mon Jul 27 2026 ...DENSE FOG ADVISORY REMAINS IN EFFECT UNTIL 8 AM CDT THIS MORNING... ...HEAT ADVISORY REMAINS IN EFFECT UNTIL 9 PM CDT THIS EVENING... * WHAT...For the Heat Advisory, peak heat index values up to 100 to 110 degrees expected. For the Dense Fog Advisory, visibility less than one quarter mile in dense fog. * WHERE...Boone, Kane, Kendall, and McHenry Counties. * WHEN...For the Dense Fog Advisory, until 8 AM CDT this morning. For the Heat Advisory, until 9 PM CDT this evening. * IMPACTS...Hot temperatures and high humidity may cause heat illnesses. Low visibility could make driving conditions hazardous. 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. If driving, slow down, use your headlights, and leave plenty of distance ahead of you.

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