KILLER TWISTERS STRIKE WASHINGTON AREA
September 25, 2001 With a ferocity
normally seen in "Tornado Alley" states such as Kansas
and Oklahoma, a supercell storm system roared through the Washington,
D.C., metropolitan area spawning an F-3 tornado, with winds between
158-206 mph, that claimed two lives at the University of Maryland
and blew down tents at the site of the Pentagon terrorist attack.
There was also an F-1 tornado that hit The Plains, Va. The Fujita tornado intensity
scale runs F0-F5. (Click NOAA satellite image for larger
view of storm system that struck the Washington, D.C., area on
Sept. 24, 2001.)
To assess the extent of this tornadic event, Travers accompanied National Weather Service meteorologists on a storm survey early Tuesday in Maryland and Virginia. An official assessment is due sometime Wednesday.
"The supercell was part
of a large weather system bringing rain from the Carolinas all
the way to Pennsylvania and New York," said NWS meteorologist
Chris Strong from the Baltimore-Washington office. "The
cell formed a tornado with a damage path stretching about 45
miles with the greatest impact near College Park, Beltsville
and Laurel, Md." It
An earlier, but not as powerful, tornado touched down in Culpepper County, Va.
At the Pentagon, tents set up by the media covering the terrorist strike were blown down. A three-story brick house was leveled in Culpepper, and 30 townhouses had roofs removed or damaged by the storm. Notebook papers and other materials from the University of Maryland, where the fatalities occurred, were found about 20 miles away in Howard County, Md.
The National Weather Service had been monitoring the storm system since Saturday morning when NOAA's Storm Prediction Center in Norman, Okla., forecast the possibility of severe weather. On Monday, the SPC followed up with a tornado watch three-and-a-half hours in advance of the strikes. The National Weather Service's Baltimore-Washington Forecast Office in Sterling, Va., issued tornado warnings, which were coordinated with local emergency management officials, and the Pentagon Joint Operations Incident Support Team.
The SPC issues a "severe thunderstorm watch," or a "tornado watch" when conditions are favorable for severe thunderstorms and tornadoes. The National Weather Service issues a "warning" when a severe storm, or tornado has been sighted on radar.
"It was clear from our Doppler radar that we were looking at a tornadic event. The storm was quite impressive," said Strong.
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