Tornadoes kill an average of 60 people a year in the United States, according to the National Oceanic and Atmospheric Administration. Many of the deaths are caused by flying or falling debris.
They are most common in the Central Plains and southeastern United States.
Here are the 10 deadliest tornadoes to touch down in the United States, according to figures from NOAA :
1. The "Tri-State Tornado" killed 695 people and injured 2,027. It traveled more than 300 miles through Missouri, Illinois and Indiana on March 18, 1925. It was rated an F5 at the top of the old Fujita scale (with winds of more than 260 mph).
2. The "Natchez Tornado" killed 317 people and injured 109 on May 6, 1840, along the Mississippi River in Louisiana and Mississippi. The official death toll may not have included slaves, according to the Federal Emergency Management Agency.
3. The "St. Louis Tornado" killed 255 people and injured 1,000 on May 27, 1896, in Missouri and Illinois. It had winds of between 207 mph and 260 mph.
4. The "Tupelo Tornado" killed 216 people and injured 700 on April 5, 1936, in the northeastern Mississippi city.
5. The "Gainesville Tornado" was a pair of storms that converged April 6, 1936, in Gainesville, Georgia, killing 203 people and injuring 1,600. The tornado destroyed four blocks and 750 houses in the northern Georgia town.
6. The "Woodward Tornado" wreaked havoc across parts of Texas, Oklahoma and Kansas on April 9, 1947. The storm, which killed 181 people and injured 970, reportedly was more than a mile wide in places.
7. The tornado that struck Joplin, Missouri, on May 22, 2011, killed 158 people and injured more than a thousand. The storm packed winds in excess of 200 mph and was on the ground for more than 22 miles.
8. The "Amite/Pine/Purvis Tornado" killed 143 people and injured 770 on April 24, 1908. The storm left only seven houses intact in Purvis, Mississippi, and also caused damage in Amite, Louisiana.
9. The "New Richmond Tornado" killed 117 people and injured 200 on June 12, 1899, in New Richmond, Wisconsin.
10. The "Flint Tornado" killed 115 people and injured 844 on June 8, 1953, in Flint, Michigan. The tornado was the deadliest twister ever recorded in the state.