The Enhanced Fujita Scale is used to assign tornadoes a rating based on estimated wind speeds and damage.
The EF Scale became operational on Feb. 1, 2007. It was revised from the original Fujita Scale, developed in 1971 by Tetsuya Fujita, to better reflect wind speed with damage observed in tornado surveys.
Deadly Severe Weather Facts & Safety Tips:
A tropical threat from the Atlantic on the United States and Caribbean islands may increase into next week.
United States residents may pay higher heating costs this fall as colder air is expected to grip the Rockies and Plains at times and some quick-hitting chilly shots may impact the Northeast.
Rescue efforts are underway in Hiroshima, Japan, after several landslides buried people and caused severe damage on Wednesday morning, local time.
Monsoonal moisture from the tropics is bringing heavy rainfall to the Phoenix area and other parts of the Southwest.
A long-lived and intense thunderstorm dumped hail that ended up being measured in feet in some parts of Mexico City Sunday afternoon and evening.
A zone of thundery rain with the risk of flooding and travel delays will occur into the weekend from the northern Plains to the central Appalachians and part of the mid-Atlantic.
W-C, Virginia (1969)
Remains of Camille - 27 inches of rain in western-central VA. 151 drowned, $140 million damage.
Weirton, WV (1979)
Worst flash flood in 20 years. At least 3 inches of rain near Weirton, WV. A number of homes were flooded and a bridge was washed out. A 4-6 block area of Weirton was inundated by several feet of water.
Tallageda, AL (1980)
At the airport, a tornado hit, overturning 6 planes and destroying 3 of them. The airport's hangars also sustained damage.