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.
following are facts about tornadoes:
- They may strike quickly, with
little or no warning.
- They may appear nearly transparent
until dust and debris are picked up
or a cloud forms in the funnel.
- The average tornado moves Southwest
to Northeast, but tornadoes have been
known to move in any direction.
- The average forward speed of a tornado
is 30 MPH, but may vary from stationary
to 70 MPH.
- Tornadoes can accompany tropical storms
and hurricanes as they move onto land.
- Waterspouts are tornadoes that form
- Tornadoes are most frequently reported
east of the Rocky Mountains during
spring and summer months.
- Peak tornado season in the southern
states is March through May; in the
northern states, it is late spring
through early summer.
- Tornadoes are most likely to occur
between 3 p.m. and 9 p.m., but can
occur at any time.
Before a Tornado
be alert to changing weather conditions.
- Listen to NOAA
Weather Radio or to commercial radio
or television newscasts for the latest
- Look for approaching storms.
Familiarize yourself with these terms
to help identify a tornado hazard:
Tornadoes are possible. Remain alert
for approaching storms. Watch the
sky and stay tuned to NOAA Weather Radio,
commercial radio, or television
A tornado has been sighted or indicated
by weather radar. Take shelter
Look for the following danger signs:
often greenish sky
- Large hail
- A large, dark, low-lying cloud (particularly
- 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!
you are in a structure (e.g. residence,
small building, school, nursing home,
hospital, factory, shopping center,
to a pre-designated shelter area such
as a safe room, basement, storm cellar,
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
If you are in a
vehicle, trailer, or mobile home
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.
If you are 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
- Do not get under an overpass or bridge.
You are safer in a low, flat
- 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.
Extreme windstorms in many parts of the
country pose a serious threat to buildings
and their occupants. Your residence may
be built “to code,” but that
mean it can withstand winds from extreme
events such as tornadoes and major
hurricanes. The purpose of a safe room
or a wind shelter is to provide a space
where you and your family can seek refuge
that provides a high level of protection.
You can build a safe room in one of several
places in your home:
- Your basement
- Atop a concrete slab-on-grade foundation
or garage floor
- An interior room on the first floor
Safe rooms built below ground level
provide the greatest protection,
but a safe room built in a first-floor
interior room also can provide the
necessary protection. Below-ground
safe rooms must be designed to avoid
accumulating water during the heavy
rains that often accompany severe
protect its occupants, a safe room must
be built to withstand high winds and
flying debris, even if the rest of the
residence is severely damaged or destroyed.
Consider the following when building
a safe room:
- The safe room must be adequately
anchored to resist overturning and
- The walls, ceiling, and door of the
shelter must withstand wind pressure
and resist penetration by windborne objects
and falling debris.
- The connections between all parts
of the safe room must be strong enough
to resist the wind.
- Sections of either interior or exterior
residence walls that are used as
walls of the safe room, must be separated from
the structure of the residence so
that damage to the residence will not cause
damage to the safe room.
information about Safe Rooms available
from FEMA Taking Shelter from the Storm:
Building a Safe Room Inside Your House.
L-233. Brochure providing details about
obtaining information about how to build
a wind-safe room to withstand tornado,
hurricane, and other high winds.
Shelter from the Storm: Building a
Safe Room Inside Your House. FEMA-320.
Manual with detailed information about
how to build a wind-safe room to withstand
hurricane, and other high winds
If you require more information about any
of these topics, the following are
resources that may be helpful.
Tornado Fact Sheet. L-148.
Provides safety tips for before, during,
and after a tornado
Areas in Buildings. FEMA 431.
Intended primarily to help building administrators,
architects, and engineers select the best
refuge areas in existing schools
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