Enhanced Fujita scale
The Enhanced Fujita scale is a tornado category scale used to measure tornadoes in the United States and Canada by how bad their damage is. The National Weather Service started using it on February 1, 2007 and in Canada in April 2013. The weakest tornadoes on this scale are classified EF0, and the strongest storms are classified EF5. The scale replaces the old Fujita scale in America. Tornadoes under EF5 label represent winds of 200 miles an hour or stronger. No tornadoes in the United States that happened before February 1, 2007 will have their ratings changed to the new scale.
|Example of damage|
Short for "EF-Unknown." The tornado doesn't hit anything, so there is no damage to tell how strong it is, or nobody can get to the damage to rate it.
Some damage to chimneys; branches broken off trees; sign boards damaged; some singles blown off.
|EF2||111–135||178–217||Fairly bad damage.
Roofs come off frame houses; mobile homes destroyed; big trees snapped or uprooted.
|EF4||166–200||267–322||Very bad damage.
Well-made houses leveled; buildings and other things with weak foundations blown away very far; skyscrapers and highrises destroyed.