March 18
- 1925 – The Tri-State tornado, the deadliest and longest-tracked tornado in United States history, carved a 219 mi (352 km)-long damage path across Missouri, Illinois, and Indiana, killing an estimated 695 people and injuring more than 2,000. Multiple towns were devastated: Annapolis, Missouri, Gorham, Illinois, and Griffin, Indiana were nearly completely destroyed; 234 people were killed in Murphysboro, Illinois and 127 in West Frankfort, Illinois.