How bad has this year’s tornado season been, relative to other years?
A: Extraordinarily bad, even by historical standards.
The [2011] death toll, now at more than 480, is the highest since 1953, when an outbreak of twisters across the Midwest and the Northeast claimed 519 lives.
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The tornado that struck Joplin, Mo., on Sunday, with its death toll now standing at 122, is the deadliest since the National Oceanic and Atmospheric Administration began keeping records in 1950.
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In 1995, researchers at the University of Oklahoma wanted to study the pattern of debris carried long distances by tornadoes...Most of the objects landed fairly close, 15 to 20 miles from where they started. A few traveled more than 60 miles. The farthest an object traveled was more than 150 miles.
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Normally, forecasters can place a tornado within about five miles of its touchdown point, Mr. Ferree said.
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People who live in trailers or mobile homes are 15 times as likely as those in permanent housing to be killed by tornadoes.
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While there has been some debate about whether it is safe to remain in a car — one study in 2002 suggested it might at least be safer than remaining in a mobile home — most experts say that it is practically impossible to outrun a tornado and that remaining in a car is dangerous. It is best to get out and seek shelter — in the basement of a building, if possible, or in a ditch or other low-lying area away from trees. Experts say that the idea that huddling under a highway overpass will provide a measure of safety is also false. The high winds can just as easily blow under the overpass as over it.