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- Scientists said Monday that they had
measured the fastest wind speed ever recorded, 318 mph, during a tornado
May 3 in the suburbs of Oklahoma City.
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- The record-setting wind occurred about
7 p.m. near Moore, where the tornado killed four people and destroyed about
250 houses.
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- The wind speed was measured with a truck-mounted
Doppler radar.
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- The fastest speed previously measured
was 286 mph clocked by a portable Doppler radar April 26, 1991, in a tornado
near Red Rock, Okla.
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- Joshua Wurman of the University of Oklahoma
says he and his research team were about a half-mile away when the tornado
was born.
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- The 318-mph speed would put the tornado
only 1 mph below an F-6 on the 0-to-6 Fujita scale. No tornado has ever
been classified an F-6.
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- Because direct measurements of tornado
winds are rare, meteorologists have used the severity of damage to classify
tornadoes. Conventional wind instruments cannot withstand powerful twisters,
and scientists are just beginning to make close-up measurements with Doppler
radars.
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- Wurman says the 318-mph winds probably
were a couple of hundred feet above the ground, not at ground level where
the twister was doing the damage that later led the National Weather Service
to classify the storm as an F-5.
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- "We don't know this was the strongest
tornado ever, just that no other had ever been measured with faster winds,"
Wurman says.
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- Winds that powerful can rip pavement
from roads, grass from the ground and freight cars from train tracks.
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- After taking the measurement, the Doppler
radar trucks followed the tornado to nearby Del City, "where it died
very quickly," Wurman says.
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- "We went through the damage a minute
or two after the tornado. It was rough driving."
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- Bob Sheets, former director of the National
Hurricane Center, says that "the ability to make such measurements
is quite a breakthrough." The methods will "help solve the mysteries
of both tornadoes and hurricanes."
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