After leaving Missouri, the Tri-State Tornado crossed into Illinois. On March 18, 1925, its long track carried it northeastward from southeastern Missouri across southern Illinois before it continued into southern Indiana.
The tornado entered Illinois near the Mississippi River and devastated communities including Gorham, Murphysboro, De Soto, West Frankfort, and Princeton. Illinois suffered the largest share of the disaster’s deaths: contemporary historical summaries record 588 fatalities in the state, compared with 12 in Missouri and 95 in Indiana.
The name “Tri-State” refers to the three states along the commonly accepted track: Missouri, Illinois, and Indiana. Arkansas was not on the tornado’s path, while Kentucky was nearby but not one of the states crossed by the principal track. The event occurred during a wider tornado outbreak, so not every storm reported in the region belonged to this one tornado.