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Flash Flood — McLean, IL

Aug 8, 2021

Flood Cause
Heavy Rain

An outflow boundary from previous convection triggered several clusters of strong thunderstorms across north-central Illinois during the late afternoon and evening of August 8th. Thanks to copious atmospheric moisture and the slow-movement of the storms, very heavy rainfall of 6 to 8 inches was observed across northwestern McLean County...including 8.25 in the town of Danvers. As a result, significant flash flooding occurred from Danvers to Carlock just northwest of Bloomington-Normal. In add

Source: NOAA National Weather Service Storm Events Database (event 978266). Narrative written by NWS staff at the time of the event.

Flood Risk Context for McLean, IL

This event is one of many recorded floods in McLean County. See the full FEMA flood zone map, NFIP claim totals, and disaster history for the area.

View McLean County flood data →

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