While the Great Plains states are known for tornado activity, tornadoes frequently occur in Illinois with numbers that are comparable to those in "tornado alley". Here are several maps showing the geographic distribution of tornadoes across the Chicago area, Illinois, and the U.S. for selected time periods. These maps were generated using data through 2004 and software from the NOAA Storm Prediction Center. The files from 1950-1998 were from an earlier study.
![]() Chicago tornado touchdowns 1950-1998 |
![]() Chicago tornado tracks 1950-2004 |
![]() Chicago tornado tracks 1985-2004 |
![]() Chicago tornado tracks 1995-2004 |