FEMA's nightmare scenario: An EF5 tornado in Dallas

[RandySF]

Meteorologist Gary Woodall calls it "our nightmare scenario" – a hugely powerful tornado sweeping through downtown Dallas at rush hour, tossing cars like toys, peeling the skin off buildings and raining "a blizzard of lethal debris" on a desperate city.

Most nightmarish of all is the title of the Weather Channel's new series of worst-case storms: It Could Happen Tomorrow.

It could.

For its next episode, scheduled for 8:30 p.m. Sunday, the Weather Channel takes the tornado that devastated Moore, Okla., in 1999 and aims it at Dallas.

Dallas emergency officials and meteorologists from the National Weather Service got their first look at the broadcast Tuesday at City Hall.

As in Moore, the tornado chews a path of destruction a mile wide and 30 miles long. The winds replicate those of the tornado that hit Moore, F5 on the Fujita scale, or 261 to 318 mph. But the toll is far greater.

Mr. Woodall, warning coordination meteorologist with the weather service's Fort Worth office, doesn't disagree with the video's premise.

The tornado that tore through downtown Fort Worth in 2000 was rated an F3, with winds of 158 to 206 mph, Mr. Woodall said. But those winds were actually west of Fort Worth.

"It was an F0-F1 in downtown," he said, and it still caused incredible damage.

Fortunately, the most violent tornadoes, F4 and F5 storms, make up only about 1 percent of all tornadoes in the U.S.

F5 is 'very rare'

"And most of those are F4s," Mr. Woodall said. "F5s are very rare, but not impossible."

Mr. Woodall, who spends much of the late winter and early spring crisscrossing northeastern Texas to visit local emergency preparedness officials and stopping at every newspaper office and radio station he can find, said the Weather Channel's tornado show would make his job easier.

"It's one thing for us to talk about it," he said, "but the show's graphics let us show it."

Dallas emergency officials were similarly pleased that the Weather Channel is bringing attention to preparedness.

"I think they did a pretty good job of showing what could happen in a worst-case scenario," said Jerry Martin of the Office of Emergency Management.

Greg Forbes, the Weather Channel's severe-weather expert for tornadoes and serious thunderstorms, said the show is based in part on a study done by the North Central Texas Council of Governments.

"They did a whole series of simulations – if the path went this way or that, the time of day, the worst-case scenarios," Dr. Forbes said. "And the major concern was: What happens if a lot of people get caught in rush-hour traffic when a tornado hits?"

The Oklahoma storm pounded Moore with torrential rain and 3-inch chunks of hail, conditions that would jam Dallas' busy highways.

"That's a big problem, that concentration of people in automobiles," Dr. Forbes said.

An F4 or F5 tornado can toss cars the length of a football field. Strong, well-built houses would be scoured from their pads. Wind would rip the glass walls from high-rises, and all the contents – desks, computers – would whip through offices, battering everything in their path.

"It'll be a deadly blender of destruction," Dr. Forbes said.

http://www.theweathervane.info/forums/f14/what-would-happen-if-super-tornado-518.html

[madrchsod]

1. syfy runs a made for tv movie about the same thing every couple of months