The Tri-State Tornado - Mar 18, 1925 - HISTORY.com

The worst tornado in U.S. history passes through eastern Missouri, southern Illinois, and southern Indiana, killing 695 people, injuring some 13,000 people, and causing $17 million in property damage. Known as the “Tri-State Tornado,” the deadly twister began its northeast track in Ellington, Missouri, but southern Illinois was the hardest hit. More than 500 of the total 695 people who perished were killed in southern Illinois, including 234 in Murphrysboro and 127 in West Frankfort.

A tornado is a dark, funnel-shaped cloud containing violently rotating air that develops in climate conditions that, in the United States, are generally unique to the central and southern plains and the Gulf states. The rotating winds of tornadoes can attain velocities of 300 mph, and its diameter can vary from a few feet to a mile. A tornado generally travels in a northeasterly distance at speeds of 20 to 40 mph and usually covers anywhere between one and more than 100 miles.

The Tri-State Tornado of 1925–which traveled 219 miles, spent more than three hours on the ground, devastated 164 square miles, had a diameter of more than a mile, and traveled at speeds in excess of 70 mph–is unsurpassed in U.S. history.