Flash Flood — Sangamon, Illinois

2010-05-26 · near Grandview, Sangamon, Illinois

Event narrative

A nearly stationary thunderstorm produced around 4.50 inches of rain in 90 minutes over the city of Springfield just before the evening rush hour. The downtown suffered major impacts with extensive flooding of streets and up to 7 feet of water under viaducts. Most streets were impassable, which resulted in more than 200 stranded vehicles. Nearly 650 homes and businesses sustained flood damage. Several people had to be rescued from the their flooded autos, but there were no injuries or fatalities.

Wider weather episode

Widely scattered thunderstorms developed during the afternoon of May 26th. Due to an extremely moist environment and weak steering winds aloft, the storms were slow-moving in nature and produced copious amounts of rainfall. Between 4 and 5 inches of rain fell in Springfield in about 90 minutes, causing widespread flash-flooding which impacted hundreds of homes, businesses, and autos. In addition, some of the other storms in central and east central Illinois produced large hail, damaging wind gusts and flash flooding.

View location on OpenStreetMap → (39.8205, -89.6869)

Source: NOAA Storm Events Database, event_id 237557. Narrative written by the NWS forecast office that issued the report.