<P> This article lists various tornado records . The most extreme tornado in recorded history was the Tri-State Tornado , which spread through parts of Missouri , Illinois , and Indiana on March 18 , 1925 . It is considered an F5 , though tornadoes were not ranked on any scale in that era . It holds records for longest path length at 219 miles ( 352 km ) , longest duration at about 31⁄2 hours , and fastest forward speed for a significant tornado at 73 mph ( 117 km / h ) anywhere on Earth . In addition , it is the deadliest single tornado in United States history with 695 fatalities . It was also the third - costliest tornado in history at the time , but has been surpassed by several others non-normalized . When costs are normalized for wealth and inflation , it still ranks third today . </P>
<P> This article lists various tornado records . The most extreme tornado in recorded history was the Tri-State Tornado , which spread through parts of Missouri , Illinois , and Indiana on March 18 , 1925 . It is considered an F5 , though tornadoes were not ranked on any scale in that era . It holds records for longest path length at 219 miles ( 352 km ) , longest duration at about 31⁄2 hours , and fastest forward speed for a significant tornado at 73 mph ( 117 km / h ) anywhere on Earth . In addition , it is the deadliest single tornado in United States history with 695 fatalities . It was also the third - costliest tornado in history at the time , but has been surpassed by several others non-normalized . When costs are normalized for wealth and inflation , it still ranks third today . </P>
what was the worst tornado to hit the united states
what was the worst tornado to hit the united states
F5
F5