 Tornado warnings, sirens went off. Multiple twisters were reported in the Chicago area. Officials say at least one person was killed. Storms downed trees and electricity poles in Illinois, Iowa, and Indiana. More than 460,000 customers lost electricity. Meanwhile, a heat wave continues to grip much of the U.S. with the National Weather Service. Here's meteorologist Frank Pereira saying there's no relief in the southeast. We're expecting temperatures today...