FEMAs Are You Ready? - About Tornadoes
Tornadoes are nature's most violent storms. Spawned from powerful
thunderstorms, tornadoes can cause fatalities and devastate a neighborhood in
seconds. A tornado appears as a rotating, funnel-shaped cloud that extends from
a thunderstorm to the ground with whirling winds that can reach 300 miles per
hour. Damage paths can be in excess of one mile wide and 50 miles long. Every
state is at some risk from this hazard.
Some tornadoes are clearly visible, while rain or nearby low-hanging clouds
obscure others. Occasionally, tornadoes develop so rapidly that little, if any,
advance warning is possible.
Before a tornado hits, the wind may die down and the air may become very still.
A cloud of debris can mark the location of a tornado even if a funnel is not
visible. Tornadoes generally occur near the trailing edge of a thunderstorm. It
is not uncommon to see clear, sunlit skies behind a tornado.
The following are facts about tornadoes:
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They may strike quickly, with little or no warning.
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They may appear nearly transparent until dust and debris are picked up or a
cloud forms in the funnel.
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The average tornado moves Southwest to Northeast, but tornadoes have been known
to move in any direction.
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The average forward speed of a tornado is 30 MPH, but may vary from stationary
to 70 MPH.
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Tornadoes can accompany tropical storms and hurricanes as they move onto land.
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Waterspouts are tornadoes that form over water.
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Tornadoes are most frequently reported east of the Rocky Mountains during
spring and summer months.
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Peak tornado season in the southern states is March through May; in the
northern states, it is late spring through early summer.
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Tornadoes are most likely to occur between 3 p.m. and 9 p.m., but can occur at
any time.
Know the Terms
Familiarize yourself with these terms to help identify a tornado hazard:
- Tornado Watch
Tornadoes are possible. Remain alert for approaching storms. Watch the sky and
stay tuned to NOAA Weather Radio, commercial radio, or television for
information.
- Tornado Warning
A tornado has been sighted or indicated by weather radar. Take shelter
immediately.
Take Protective Measures
Before a Tornado
Be alert to changing weather conditions.
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Listen to NOAA Weather Radio or to commercial radio or television newscasts for
the latest information.
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Look for approaching storms.
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Look for the following danger signs:
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Dark, often greenish sky
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Large hail
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A large, dark, low-lying cloud (particularly if rotating)
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Loud roar, similar to a freight train.
If you see approaching storms or any of the danger signs, be prepared to take
shelter immediately.
During a Tornado
If you are under a tornado WARNING, seek shelter immediately!
|
If you are in: |
Then: |
| A structure (e.g. residence, small building, school, nursing home,
hospital, factory, shopping center, high-rise building) |
Go to a pre-designated shelter area such as a safe room, basement,
storm cellar, or the lowest building level. If there is no basement, go to the
center of an interior room on the lowest level (closet, interior hallway) away
from corners, windows, doors, and outside walls. Put as many walls as possible
between you and the outside. Get under a sturdy table and use your arms to
protect your head and neck. Do not open windows. |
| A vehicle, trailer, or mobile home |
Get out immediately and go to the lowest floor of a sturdy, nearby
building or a storm shelter. Mobile homes, even if tied down, offer little
protection from tornadoes. |
| The outside with no shelter |
Lie flat in a nearby ditch or depression and cover your head with
your hands. Be aware of the potential for flooding.
Do not get under an overpass or bridge. You are safer in a low, flat location.
Never try to outrun a tornado in urban or congested areas in a car or truck.
Instead, leave the vehicle immediately for safe shelter.
Watch out for flying debris. Flying debris from tornadoes causes most
fatalities and injuries. |