Flash Flood — Effingham, Illinois

2025-07-20 to 2025-07-21 · near Altamont, Effingham, Illinois

Event narrative

Water was flowing across Main Street between Division Street and Oak Street.

Wider weather episode

An outflow boundary interacting with a very moist airmass characterized by surface dewpoints in the middle to upper 70s triggered clusters of strong to severe thunderstorms across south-central Illinois during the afternoon and evening of July 20th. Scattered wind damage and flash flooding occurred...mainly south of a Shelbyville to Marshall line.

View location on OpenStreetMap → (39.0595, -88.7488)

Source: NOAA Storm Events Database, event_id 1276252. Narrative written by the NWS forecast office that issued the report.