The most powerful tornado to ever hit the Chicago area struck without warning over 25 years ago today: http://go.wgntv.com/1NUtUx2 | WGN TV

On Aug. 28, 1990, an F5 tornado ripped through Plainfield, leaving a swath of destruction. Twenty-nine people were killed and some 300 others were injured. The tornado touched down outside Oswego about 3:15 p.m., and the 200 mph winds inside it etched a scar 16 miles long, stretching to the southwest side of Joliet. Half an hour later, it was over. It remains the only F5 tornado ever to hit the Chicago area. See more photos from the aftermath here: http://trib.in/2vmxSjj | Chicago Tribune