Two people were critically injured Friday when a strong line of storms raked the Chicago area, bringing down trees and power lines, knocking out power to thousands, and delaying the travel of thousands of commuters heading into a busy holiday weekend.
In one incident, a woman sitting on a couch was injured when the roof collapsed on her. The building she was in, on the 1100 block of North Ashland Avenue, was under construction at the time, officials said.
She was taken to John H. Stroger Jr. Hospital of Cook County and listed in critical condition as of 7:30.
On the northwest side of the city, a man was taken to Lutheran General Hospital and listed in critical condition after he was struck by a falling tree on the 7200 block of West Howard Street, officials said.
Temperatures in the Chicago area on Friday were in the upper 90s, and with high humidity the heat index was more than 100 degrees. All of that hot, humid air was fuel for the line of storms that began crossing the Wisconsin/Illinois state line in mid-afternoon.
The storms topped out at about 55,000 feet and were moving to the south and east at about 25 MPH at about 5 p.m.
Wind gusts exceeded 60 MPH in some areas and there were reports of 12 to 18-inch diameter trees down in northern suburbs. Other areas saw large hail stone falling from the sky. One of NBC Chicago's neighborhood weather sites, in Harvard, Ill., collected 3.8 inches of rainfall from the event.
Thousands of lightning strikes were recorded. Residents were advised to get inside a sturdy structure or hard-roofed automobile until the severe weather passed.
Reminder: there is no safe place outside when there is lightning, and lightning strikes are possible up to 30 minutes after a storm passes.
Full ground stops were issued at both O'Hare International and Midway International while the brunt of the storm passed overhead.
On roadways throughout the area, traffic slowed to a crawl as torrential rain diminished visibility.
As of 9 p.m., Commonwealth Edison officials reported nearly 71,000 customers were without power.
Storms are expected to continue to push southward into the southern suburbs during the Friday evening hours.