Picture of a May 11, 1991, tornado in Cimarron County, Oklahoma
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Greg Stumpf

Tornadoes

Tornadoes form from severe thunderstorms. They have a very high energy density which means that they are very destructive to a small area. They also don't last very long which makes them hard to study. Without much information about how they develop, meteorologists have a hard time forecasting when they'll form. The general public knows even less about tornadoes, which is why there are so many inaccurate myths about them.

75% of the world's tornadoes occur in the United States, but they can (and probably have) developed anywhere. Most tornadoes in the U.S. form in an area of the Great Plains known as Tornado Alley. There are also some other interesting facts about tornadoes.

People with an interest in tornadoes sometimes attend classes held by the National Weather Service to become trained as tornado spotters. Sometimes people travel out to Tornado Alley to chase tornadoes either to research these powerful storms or to photograph them. When a tornado touches down, scientists try and figure out how strong it was by using the Enhanced Fujita Tornado Scale.
Last modified August 1, 2008 by Vanessa Pearce.

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