The National Weather Service now estimates that at least three tornadoes touched down in the Chicago area during an outbreak of severe weather on Saturday, with straight-line winds also causing damage in Rockford.
One of the three EF-0 tornadoes touched down in suburban Oak Brook, officials say, while the other two tornadoes touched down in different parts of Boone County.
The first tornado touched down in Oak Brook near a Hilton hotel and the Willow Crest Golf Club, officials said. This tornado, rated as an EF-0 tornado on the Enhanced Fujita Scale, reached estimated maximum wind speeds of 75 miles per hour and reached a maximum width of 60 meters.
The tornado was on the ground for about 1.9 miles, and while there it snapped tree branches and caused the roof of an outbuilding on the golf course to collapse. He stayed on the ground for three minutes before getting up.
A second EF-0 tornado was reported in Boone County near Timberlane. This tornado, which reached an estimated maximum wind speed of 80 miles per hour, remained on the ground for about a minute at 5:55 p.m. and traveled half a mile, reaching a maximum width of 60 meters.
Several trees were uprooted and snapped early in the tornado’s path, and several floating docks were tossed onto Candlewick Lake, officials said.
A third tornado was reported about 12 minutes later in Capron. The extremely brief tornado touched down in an open field near the intersection of Coon Trail and Capron roads, and caused no known damage, with unknown wind speed and width.
Officials also said that after a thorough investigation, using drone imagery from the Rockford Fire Department and Doppler radar data from Chicago and Milwaukee, the storm damage in Rockford was not caused by a tornado, but with straight-line winds that blew over 70 miles. per hour.
Straight-line winds caused the roof of a building to collapse near the intersection of 9and and the streets of Broadway in Rockford. The winds also caused additional roof damage to other buildings and snapped utility poles and tree branches in the area.
All data is preliminary and subject to change.