Weather service staff surveyed the damage caused by Tuesday night's severe weather in Walworth County and determined a EF-1 twister touched down.
The severe weather damaged a number of buildings in a small industrial park in the Town of Lyons. The tornado left a trail of tree damage north of Lake Geneva.
PHOTOS: Funnel clouds spotted in Chicago area
At least two tornado touchdowns were reported in Livingston County as severe storms ripped through the Chicago area on Tuesday.
Law enforcement officials reported two brief tornado touchdowns near Cornell around 4:30 p.m. and near Pontiac around 5 p.m. National Weather Service teams will survey the area to confirm if any tornadoes touched down.
Livingston County Emergency Management spokesperson Charles Schopp said there were no reports of any damage from the storms in Cornell or Pontiac. He said the area is very rural.
Funnel clouds were spotted Tuesday afternoon in several areas, including Streator and Lexington, which is near Pontiac.
The Associated Press contributed to this report.