The deadliest tornado in recorded U.S. history occurred 100 years ago. The Tri-State Tornado touched down in southeastern Missouri on March 18, 1925.

Tuesday will mark a somber anniversary, as it will be 100 years since the deadliest tornado in the country’s history hit Illinois.

Communities across Missouri, Illinois, and Indiana were devastated by the deadliest and longest-running tornado ever recorded a century ago. Here's what happened.

Violent tornadoes ripped through parts of the U.S., wiping out schools and toppling semitractor-trailers in several states.

A dangerous tornado outbreak which started on Friday evening continued into the first half of the weekend with nearly 2 dozen deaths across the nation's heartland and South.

Portions of West Virginia, Ohio and Pennsylvania were under a new tornado watch issued on Sunday by the National Weather Service, as the death toll from storms rose to at least 34 people in six states since Friday.