Since 1950, there have been 271 tornadoes recorded across the Chicago area, according to the National Oceanic and Atmospheric Administration.
The deadliest tornado hit on April 21, 1967, traveling through Oak Lawn and the South Side of Chicago, killing 33 and injuring 500, part of a series of at least 10 tornadoes that killed and injured even more. It was an F4 on the Fujita scale, which means its winds were between 207 and 260 mph. Estimates were it did about $2.5 million in damage.
The most costly tornado was an F5 — wind speeds between 261 and 318 mph — that formed near Oswego and passed through Plainfield, Crest Hill, and Joliet, destroying between $165 million and $250 million worth of property on Aug. 28, 1990. It also killed 29 people and injured 353.
Below you can explore these tornadoes, which are color-coded by their F scale rating, which is an estimation of wind speeds based on damage intensity.
Note: The F scale was replaced by the Enhanced F scale (EF Scale) in February 2007.