The most extreme tornado in recorded history was the Tri-State Tornado, which roared through parts of Missouri, Illinois, and Indiana on March 18, 1925. It was likely an F5, though tornadoes were not ranked on any scale in that era. It holds records for longest path length (219 miles, 352 km), longest duration (about 3.5 hours), and fastest forward speed for a significant tornado (73 mph, 117 km/h) anywhere on earth. In addition it is the deadliest single tornado in United States history (695 dead). It was also the second 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.
The deadliest tornado in world history was the Daultipur-Salturia Tornado in Bangladesh on April 26, 1989, which killed approximately 1,300 people. Bangladesh has had at least 19 tornadoes in its history kill more than 100 people, almost half of the total in the rest of the world.
The most extensive tornado outbreak on record, in almost every category, was the Super Outbreak, which affected a large area of the central United States and extreme southern Ontario in Canada on April 3 and April 4, 1974. Not only did this outbreak feature an incredible 148 tornadoes in only 18 hours, but an unprecedented number of them were violent; 6 were of F5 intensity and 24 were F4. This outbreak had a staggering 16 tornadoes on the ground at the same time at the peak of the outbreak. More than 300 people, possibly as many as 330, were killed by tornadoes during this outbreak. However, this record was later broken during the 2011 Super Outbreak, which resulted in 340+ casualties and had more than 330 tornadoes touch down.