EF1 tornado in Henry County, Illinois

An NWS Storm Survey found that an EF-1 tornado with peak winds of 100 MPH and was 200 yards wide caused extensive tree damage occurred through the city of Kewanee. Many homesteads had minor roof damage. A couple of the homes had large sections of the roofs removed.

Thunderstorms rapidly developed over northern Iowa during the afternoon and organized into a powerful line of wind producing storms that surged through the Quad Cities and into northern and central Illinois through the evening hours. These storms brought widespread damaging winds up to 100 mph for many locations, extending across eastern Iowa, much of Illinois, and into Indiana. The Storm Prediction Center has classified this event as a Derecho which by definition is a swath of wind damage at least 400 miles long and at least 60 miles wide including several well-separated significant wind gusts over 75 mph. Corridors of significant wind damage occurred along Highway 20. 10 tornadoes also occurred with these storms in the NWS Quad Cities service area.

In addition to the wind, very heavy rainfall fell in a short amount of time with many locations seeing over an inch. The highest totals fell in McDonough and Warren counties in Illinois where amounts between 2 and 3 inches fell.