Safety - Before, During, and After
Follow lightning and severe thunderstorm safety and preparedness
actions as well as the information provided below. The following
information is from Roger
Edwards (NWS SPC Norman, OK) http://www.spc.noaa.gov/faq/tornado/#Safety
There is no such thing as guaranteed safety inside a tornado. Freak accidents
happen; and the most violent tornadoes can level
and blow away almost any house and its occupants. Extremely violent
F5 tornadoes are very rare, though. Most tornadoes are actually much weaker
and can be survived using these safety ideas...
PREVENTION AND PRACTICE
BEFORE THE STORM...
At home, have a family tornado plan in place,
based on the kind of dwelling you live in and the safety tips below.
Know where you can take shelter in a matter of seconds, and practice
a family tornado drill at least once a year. Have a pre-determined
place to meet after a disaster. Flying
debris is the greatest danger in tornadoes; so store protective
coverings (e.g., mattress, sleeping bags, thick blankets, etc) in
or next to your shelter space, ready to use on a few seconds' notice.
When a tornado watch is issued,
think about the drill and check to make sure all your safety supplies
are handy. Turn on local TV, radio or NOAA Weather Radio and stay
alert for warnings. Forget about the old notion of opening windows
to equalize pressure; the tornado will blast open the windows for
you! If you shop frequently at certain stores, learn where there
are bathrooms, storage rooms or other interior shelter areas away
from windows, and the shortest ways to get there. All administrators
of schools, shopping centers, nursing homes, hospitals, sports arenas,
stadiums, mobile home communities and offices should have a tornado
safety plan in place, with easy-to-read signs posted to direct everyone
to a safe, closeby shelter area. Schools and office building managers
should regularly run well-coordinated drills. If you are planning
to build a house, especially east of the Rockies, consider an underground
tornado shelter or an
interior "safe room".
Know the signs of a tornado:
Weather forecasting science is not perfect and some tornadoes do
occur without a tornado warning. There is no substitute for staying
alert to the sky. Besides an obviously
visible tornado, here are some things to look and listen for:
- Strong, persistent rotation in the cloud base.
- Whirling dust or debris on the ground under a cloud base -- tornadoes sometimes
have no funnel!
- Hail or heavy rain followed by either dead calm or a fast, intense wind shift. Many tornadoes are wrapped in heavy precipitation and can't be seen.
- Day or night - Loud, continuous roar or rumble, which doesn't fade in a few seconds like thunder.
- Night - Small, bright, blue-green to white flashes
at ground level near a thunderstorm (as opposed to silvery lightning
up in the clouds). These mean power lines are being snapped by very
strong wind, maybe a tornado.
- Night - Persistent lowering from the cloud base, illuminated
or silhouetted by lightning -- especially if it is on
the ground or there is a blue-green-white power flash underneath.
WHAT TO DO IF A TORNADO WARNING IS ISSUED
OR YOU SEE A TORNADO...
In a house with a basement: Avoid windows.
Get in the basement and under some kind of sturdy protection (heavy
table or work bench), or cover yourself with a mattress
or sleeping bag. Know where very heavy objects rest on the floor above
(pianos, refrigerators, waterbeds, etc.) and do not go under them.
They may fall down through a weakened floor and crush you.
In a house with no basement, a dorm,
or an apartment:
Avoid windows. Go to the lowest floor, small center room (like a
bathroom or closet), under
a stairwell, or in an interior hallway with no windows. Crouch
as low as possible to the floor, facing down, and cover your head
with your hands. A bath tub may offer a shell of partial protection.
Even in an interior room, you should cover yourself with some sort
of thick padding (mattress, blankets, etc.), to protect against
falling debris in case the roof and ceiling failure.
In an office building, hospital,
nursing home or skyscraper: Go
directly to an enclosed, windowless area in the center of the building
-- away from glass and on the lowest floor possible. Then,
crouch down and cover your head. Interior stairwells are usually
good places to take shelter, and if not crowded, allow you to get
to a lower level quickly. Stay off the elevators; you could be trapped
in them if the power is lost.
In a mobile home:
Get out! Even if your home is tied down, you are probably safer
outside, even if the only alternative is to seek shelter out in
the open. Most tornadoes can destroy even tied-down mobile homes,
and it is best not to play the low odds that yours will make it.
If your community has a tornado shelter, go there fast. If there
is a sturdy permanent building within easy running distance, seek
shelter there. Otherwise, lie flat on low ground away from your
home, protecting your head. If possible, use open ground away from
trees and cars, which can be blown onto you.
At school: Follow
the drill! Go to the interior hall or room in an orderly way as
you are told. Crouch low, head down, and protect the back of your
head with your arms. Stay away from windows and large open rooms
like gyms and auditoriums.
In a car or truck:
Vehicles are extremely dangerous in a tornado. If the tornado is
visible, far away, and the traffic is light, you may be able to
drive out of its path by moving at right angles to the tornado.
Otherwise, park the car as quickly and safely as possible -- out
of the traffic lanes (it is safer to get the car out of mud later
if necessary than to cause a crash). Get out and seek shelter in
a sturdy building. If in the open country, run to low ground away
from any cars (which may roll over on you). Lie flat and face-down,
protecting the back of your head with your arms. Avoid
seeking shelter under bridges, which can create deadly traffic
hazards while offering little protection against flying debris.
In the open outdoors:
If possible, seek shelter in a sturdy building. If not, lie flat
and face-down on low ground, protecting the back of your head with
your arms. Get as far away from trees and cars as you can; they
may be blown onto you in a tornado.
In a shopping mall or large store:
Do not panic. Watch for others. Move as quickly as possible to an
interior bathroom, storage room or other small enclosed area, away
from windows.
In a church or theater:
Do not panic. If possible, move quickly but orderly to an interior
bathroom or hallway, away from windows. Crouch face-down and protect
your head with your arms. If there is no time to do that, get under
the seats or pews, protecting your head with your arms or hands.
AFTER THE TORNADO...
Keep your family together and wait for emergency personnel to arrive.
Carefully render aid to those who are injured. Stay away from power
lines and puddles with wires in them; they may still be carrying
electricity! Watch your step to avoid broken glass, nails, and other
sharp objects. Stay out of any heavily damaged houses or buildings;
they could collapse at any time. Do not use matches or lighters,
in case of leaking natural gas pipes or fuel tanks nearby. Remain
calm and alert, and listen for information and instructions from
emergency crews or local officials. |
Nil <2% 
Limited 2-10%
Elevated 11-40%
Significant 41-80%
Critical >80%
Special thanks to Dr. Vince Dimiceli (ORU) for help working on this project.
