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Flood — Johnson, IL

Mar 18, 2008

Torrential rainfall amounts from 6 to 12 inches occurred over a two-day period, causing an historic flood event. A very slow-moving cold front over southwest Illinois and southeast Missouri provided the focus for prolonged heavy rainfall. A deep southwest wind flow brought subtropical moisture across the frontal zone. Two-day rainfall amounts included 11.64 inches at Anna (Union County) and 11.50 inches at Galatia (Saline County). At the Carbondale airport, the two-day total was 6.61 inches. Oth

Source: NOAA National Weather Service Storm Events Database (event 84933). Narrative written by NWS staff at the time of the event.

Flood Risk Context for Johnson, IL

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

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