Flash Flood in Logan County, Illinois

Water was flowing across Route 121 southeast of Lincoln.

Several rounds of significant convection impacted central Illinois on June 17th, 2026. Clusters of thunderstorms initially formed on the nose of a strong low-level jet streak across Iowa during the pre-dawn hours, then tracked southeastward along a warm frontal boundary into central Illinois through midday. Scattered damaging wind gusts were reported in north-central Illinois, with the most concentrated corridor of 60-70 mph winds focused along a Galesburg, to Peoria, to Chenoa line.

Thunderstorms re-developed along a remnant outflow boundary from the morning convection by mid to late afternoon, with the most intense cells materializing along and south of a Springfield to Paris line where several tornadoes occurred and hail larger than baseballs (3 diameter) was reported across portions of Moultrie, Douglas, and Coles counties. An EF2 tornado impacted the Mattoon to Charleston area, and an EF3 tracked just north of Effingham.