Hail — Effingham, Illinois

2025-09-20 · near Altamont, Effingham, Illinois

Wider weather episode

An upper-level disturbance interacting with a nearly stationary frontal boundary triggered clusters of strong thunderstorms across central Illinois during the afternoon of September 20th. A storm cell intersecting an outflow boundary over Mason County resulted in an EF-0 tornado east of Mason City. Meanwhile other storms produced hail as large as quarters and isolated minor wind damage.

View location on OpenStreetMap → (39.0555, -88.7500)

Source: NOAA Storm Events Database, event_id 1289096. Narrative written by the NWS forecast office that issued the report.