Flash Flood — Winnebago, Illinois

2025-08-18 · near Rockton, Winnebago, Illinois

Event narrative

Flash flooding impacted portions of far northeast Winnebago County, specifically in the vicinity of Rockton. Street flooding was reported near Rockton Rd and Dorr Rd with floodwater reaching into yards. Street flooding was also reported via mPing along I-39 south of McCurry Rd. A private weather station on the east side of Rockton recorded 4.5 of rainfall. Two others nearby recorded closer to 3.5.

Wider weather episode

During the afternoon and evening of the 18th, a few rounds of thunderstorms brought torrential rainfall to much of northern Illinois resulting in flash flooding. One particularly strong storm also produced damaging winds in DeKalb County. Initial reports estimate $8.8 million in flood damages around northern and northeast Illinois, and around $2.5 million in the city of Chicago alone.

View location on OpenStreetMap → (42.4574, -89.0474)

Source: NOAA Storm Events Database, event_id 1288629. Narrative written by the NWS forecast office that issued the report.