La Plata Tornado Reduced To an F4
Top Speeds Brief, U.S. Officials Say
By Michael E. Ruane
Washington Post Staff Writer
Wednesday, May 8, 2002; Page B01
The National Weather Service announced yesterday that the April 28 tornado that claimed five lives in and around La Plata was an F4 on the Fujita Damage Scale, and not an F5 as preliminary assessments had suggested.
In addition, the Weather Service said the twister reached F4 power, with wind speeds of 207 to 260 mph, for only a minute or two and only over an area about a block in size in downtown La Plata.
Across most of the storm's path, it was in the F1 and F2 range, with wind speeds ranging from 73 mph -- one mph below hurricane force -- to 157 mph.
The Weather Service said it reached its conclusions after a detailed three-day damage survey by Michael Vescio, a meteorologist from its Fort Worth office, and Tim Marshall, a volunteer wind damage expert from a Texas engineering firm, both of whom are experienced tornado evaluators.
Weather Service officials had said last week that their assessment of the tornado as a probable F5 was preliminary. F5 is the highest level on the damage scale, with wind speeds of 261 to 318 mph. "We didn't change our mind," said meteorologist John Ogren, who is leading the service's storm review. "It's a continuing assessment."
He stressed at an afternoon news conference yesterday that the storm was still a devastating force. Only 2 percent of the nation's recorded tornadoes are F4s and F5s, but they account for 70 percent of the fatalities.
"Because we're bringing it from a 5 to a 4, that's nothing to sneeze at," Ogren said at National Weather Service headquarters in Silver Spring. "This was a terrible tornado."
"Regardless of final 'F-strength,' this tornado outbreak was deadly, destroyed property and disrupted many lives throughout Southern Maryland," he said. "Tornadoes can kill at any strength, and can strike anywhere."
In La Plata, Donald P. McGuire, director of emergency services for Charles County, said that despite the downgrade, the storm "still kicked us right in the butt."
McGuire added that he believes the Weather Service, for whatever reason, is reluctant to say that an F5 could happen on the East Coast.
"I think I'm going to stick with what they said the day after the storm," McGuire said.
Ogren said the rating change came from, among other things, an almost "door-to-door" damage analysis that sought to weigh the structural integrity of buildings against the presumed power of the storm.
If, for example, a house was found destroyed on a property where the mailbox was still standing and the leaves were still on the trees, the experts might give less weight to the storm's power and more to the home's structural weakness, he said.
He said the team found a number of homes that experts call "sliders," which are swept from their foundations more easily than some others.
© 2002 The Washington Post Company
_____Tornado in La Plata_____
The Quiet After the Storm (The Washington Post, Aug 4, 2002)
Tornado Inflicted Misfortune Unevenly (The Washington Post, Aug 4, 2002)
For Victims Of Tornado, Another Blow (The Washington Post, May 28, 2002)
More Aid For Parts Of Md. Hit By Twister (The Washington Post, May 9, 2002)
Fifth Person Dies of Storm Injuries (The Washington Post, May 4, 2002)
More Damage From Tornado Found; Fourth Person Dies (The Washington Post, May 3, 2002)
For Huge Cleanup, Thousands of Helping Hands (The Washington Post, May 2, 2002)
Amid Wreckage at Damaged Churches, Members Give Thanks That Storm Didn't Take More Lives (The Washington Post, May 2, 2002)
As Tornado Struck, 'We Saw Houses Falling Apart' (The Washington Post, May 2, 2002)
Southern Md. to Get U.S. Disaster Relief (The Washington Post, May 2, 2002)
How to Get Help -- and How to Give It (The Washington Post, May 2, 2002)
Tornado's Toll Gloomier (The Washington Post, May 1, 2002)
In La Plata, a Will to Rebuild (The Washington Post, May 1, 2002)
In the Eye of History (The Washington Post, May 1, 2002)
Adjusters Quickly Bring Assessments, Answers (The Washington Post, May 1, 2002)
The F5: Mother Nature's Massive Twist of Fate (The Washington Post, May 1, 2002)
Close Calls, And Worse, In Storm's Path (The Washington Post, Apr 30, 2002)
'Absolutely Devastating' (The Washington Post, Apr 30, 2002)
Not La Plata's First or Worst (The Washington Post, Apr 30, 2002)
The Tornado's Path
Nature's Most Violent Storms
Photo Gallery: Damage in La Plata
Panorama: Tornado Damage in La Plata
Video: Tornado-Ravaged Cities Cope
Meteorologist Dewey Walston of the National Weather Service answered questions on tornadoes.