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:
Cyclonic Storm Kyant will unleash heavy rain and strong winds on parts of eastern India later this week as Diwali festivities take place.
A storm will slide in from the Midwest to bring another dose of cold rain and heavy, wet snow to parts of the northeastern United States from Wednesday night into Friday.
As many as three storms will roll in from the Pacific Ocean and bring rounds of soaking rain and high-country snow to California from late this week to early next week.
The severe drought in the northeastern U.S. has left most of the region reeling for months as farmers have been forced to work with arid land.
Dry weather is expected across much of Germany this weekend and will make for ideal conditions for viewing of autumn foliage or attending outdoor events.
Approximately one in 10 Americans may suffer from some degree of severe weather fear, including phobias related to extreme weather events, lightning and even clouds.
Chicago, IL (1997)
58 mph winds cause damage. 15 foot waves crash onto Lake Shore Drive.
Hurricane Mitch attains category 5 on Saffir-Simpson scale. 20-40 foot waves smash Honduras. Over a four day period, over 10,000 lose their lives in Central America.
New York City, NY (1859)
Earliest substantial snow -- 4 inches fell.