- ROCK CREEK, Ala. (Reuters) - The killer tornado that hit Alabama this week
was among the most powerful storms on record, meteorologists said Friday.
The tornado, spawned by a ``supercell'' thunderstorm that swept into west-central
Alabama late Wednesday, was ranked an F-5, the top of the Fujita scale
which was named after T. Theodore Fujita, a pioneer in tornado research.
The F-5 tornado, with winds ranging from 261 to 318 miles an hour is measured
by the damage it causes rather than actual wind speed because wind instruments
usually are not capable of withstanding such force.
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- ``This is as bad as it gets,'' National
Weather Service meteorologist Kevin Pence said. The F-5 tornado is capable
of lifting frame houses off their foundations, carrying cars more than
100 yards through the air and tearing chunks of asphalt off roads and grass
off lawns, according to the National Weather Service. As a comparison,
the 175-mile an hour winds of Hurricane Andrew, which caused some $25 billion
damage in south Florida in August 1992, would have ranked an F-3, in the
mid-range of the Fujita scale.
-
- Experts say there may be no safe refuge
from an F-5 for those exposed to its full force. ``Even F-4s can be unsurvivable,''
Pence said.
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- The tornado killed 30 people in Alabama's
Jefferson County and another twister from the same system killed two in
nearby St. Clair County. But early warnings may have saved thousands who
fled to basements or lower floors, officials said. Survivors, some of whom
huddled in hallways or bathrooms as the storm ripped the roof and walls
from their home, described the tornado variously as a ``thundering roar,''
a ``sonic boom,'' or a ``runaway locomotive.''
-
- ``It sounded like an airplane crashing
into our house,'' said Tammy Scott, whose three-bedroom concrete-and-brick
home was leveled by the storm.
-
- The tornado snapped 60-foot pines and
oaks in half or yanked them from the ground by their roots. It stripped
wooded hillsides clean, flattened grass and bushes and peeled bark from
trees. It twisted structural steel. Supercells are particularly violent,
long-lasting rotating thunderstorms, Pence said.
-
- ``What makes it super is that it can
last from two to eight hours. It's life span is just incredible,'' he said.
The cell that spawned the Jefferson County tornado and at least two others
in west-central Alabama may also have created tornadoes that killed at
least nine people in Georgia. It was the deadliest tornado to hit Alabama
since 1932, the National Weather Service said. The last time an F-5 tornado
hit Alabama was April 1977. The storm killed 22 people, also in Jefferson
County. ^REUTERS@
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