A storm bringing quarter-size hail and winds up to 70 miles per hour is bearing down on Elmhurst.
A severe thunderstorm warning is in effect until 4:45 p.m. for Cook and eastern DuPage Counties. At 3:45 p.m., the storm was located along a line from Carol Stream to Peotone and moving east at 50 miles per hour. The warning area includes the city of Chicago. Lollapalooza organizers have ordered an evacuation of Grant Park.
The National Weather Service is calling the storm "extremely dangerous" and is warning residents to stay away from windows and seek shelter.
A flash flood warning is in effect until 6 p.m.