Tornadoes are the nastiest kind of weather around. Only hurricanes and
floods cause more damage, and the only reason for that is that they
affect larger areas. Most kinds of houses, when hit by a tornado, will
be demolished. Nearby houses may be left untouched (or maybe not). Cars
can be lifted and thrown. Smaller items have been carried tens of miles
by tornado winds.
The biggest safety hazard from being in the path of a tornado is
being struck by flying debris, which may be traveling at hundreds of
miles per hour. Even the smallest of items, like a nail or a rock, may
turn into a deadly projectile. The best thing to do when a tornado
comes is to go down into a basement area away from windows which will
shatter and away from things that can be picked up and thrown by the
wind. Door frames are often cited as good places to be because they may
not collapse as easily and they offer some protection against debris.
It's a good idea to cover your head and eyes. A heavy mattress or
sleeping bag will help protect you from flying stuff. It is dangerous
to be either in a car or a mobile home -- you will probably be safer
outside in a low area, away from these (they could be picked up and
dropped on you, of course!).
Debris may be weak and may collapse after the tornado has passed,
presenting a different hazard. Gas and water pipes maybe broken,
creating a fire or flood hazard. Some debris may be poisonous. Be very
careful with the debris after a tornado has passed!
Here is a link to some safety instructions
from the National Oceonogrpahic and Atmospheric Administration (NOAA).
(published on 10/22/2007)