Heavy storms brought large hail, strong winds and significant amounts of rain through the suburbs Wednesday evening, and severe weather warnings continued late into the night in some areas.
A tornado watch remained in effect for Kane and McHenry counties until 11 p.m. Cook, DuPage and Lake counties were under a severe thunderstorm watch until 1 a.m. Thursday.
The National Weather Service confirmed shortly before 5 p.m. that a tornado touched down near Somonauk, about 25 miles southwest of Aurora. A severe thunderstorm capable of producing a tornado was also seen six miles west of Plainfield.
Aurora sounded its tornado sirens around 5:30 p.m. due to Kendall County being under a tornado warning, but no tornadoes were spotted within city limits, according to a news release.
The National Weather Service had said the storms with the greatest probability to produce severe weather would enter the Chicago area between 6 and 11 p.m.
As of 8:35 p.m., more than 350 flights were canceled at O'Hare International Airport, according to the Chicago Department of Aviation. Delays were between 60 to 90 minutes. At Midway International Airport, more than 50 flights had been canceled and about two dozen flights were delayed for an average of 2 hours and 30 minutes.
Multiple Metra lines experienced delayed service during the evening rush, with some trains running up to 90 minutes late. The Union Pacific North Line, Union Pacific Northwest Line and Union Pacific West Line were still having 15 to 80 minute delays as of 9 p.m.
ComEd increased its staffing levels to prepare for the storms, according to a news release.
Between Cook, DuPage, Kane, Lake and McHenry Counties, there were close to 13,000 ComEd customers without power shortly after 9 p.m., according to the company's website. Cook County had more than 9,800 customers without service, while McHenry had nearly 2,000 without service.
Customers can use the ComEd mobile app for iPhone and Android smartphones or text OUT to 26633 (COMED) to report an outage. They can also file reports at comed.com, on the company's Facebook page at facebook.com/comed, or by calling 1-800-EDISON1.
Information on outages will be updated every 30 minutes at comed.com/map.
Local events, such as RotaryFest in Elk Grove Village and the Summertime Garden Workshop and Cocktail Hour at Randhurst Village Center Court in Mount Prospect, were canceled due to the weather. The committee of the whole and city council meeting was canceled in Elgin.
The White Sox game was also canceled, as were classes and exams at Northwestern University's Chicago and Evanston campuses.
DuPage County Stormwater Management said in a news release that it would likely activate some of the county's flood control facilities, particularly for the Salt Creek and western branch of the DuPage River.