Flash Flood — Cook, Illinois

2025-08-17 · near Hegewisch, Cook, Illinois

Event narrative

Roughly 40,000 structures sustained flood damage around the city of Chicago. The greatest impacts were felt across the southwest side near and east of Midway Airport, but reports came in from all across the city. Chicago alone accounted for approximately $230 million in flood damages.

Wider weather episode

A series of thunderstorms brought torrential rainfall and widespread flooding to much of the Chicago metro area, namely the south and west suburbs and up into the city of Chicago. Several Oswego District 308 schools received water and storm damage. Flood damages were estimated at around $288 million across the metro area, most of which came from the city of Chicago which alone accounted for roughly $230 million in damages with roughly 40,000 individual structures flooded around the city. The remainder of Cook County accounted for roughly $57 million in flood damages with more than 10,000 additional structures flooded. Several instances of wind damage were also reported, mostly damage to trees.

View location on OpenStreetMap → (41.6746, -87.5265)

Source: NOAA Storm Events Database, event_id 1295012. Narrative written by the NWS forecast office that issued the report.