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Dr. Christopher S. Baird

Where is the safest place to go when a tornado hits?

Category: Earth Science      Published: April 5, 2013

Highway underpasses, cars, or near windows are not the safest places to go when a tornado hits. The safest place is an interior room on the lowest floor of a strong building, such as the basement. Public Domain Image, source: NOAA.

Contrary to popular belief, the safest place to go when a tornado hits is not under a highway overpass. This location has little to protect you from debris being thrown around by the tornado. Additionally, overpasses can collapse. Most of the damage that a tornado causes is due to its high winds knocking down structures and hurling debris like bullets. When rocks, metal signs, roof shingles, or wall studs get picked up and thrown at high velocity by the wind, they act like cannonballs. The main damage from a tornado is not due to an air pressure difference that makes sealed houses explode. For this reason, opening windows before a tornado to relieve air pressure will not lessen the damage. With these concepts in mind, the safest place to go in a tornado strike is not outside, in your car, or under a highway. Tornadoes have been known to pick up cars, trucks, and even buses. The safest place to seek shelter from a tornado is deep inside a strong building where you will be protected from flying debris and collapsing outer walls. The Federal Emergency Management Agency (FEMA) recommends the following course of action in a tornado warning: If you are in a mobile home or outside, get to a solid building as soon as possible. Once in the building, "Go to a pre-designated shelter area such as a safe room, basement, storm cellar, or the lowest building level...go to a small interior room or hallway on the lowest floor possible." Furthermore, FEMA recommends that if you can't get to a building in time, seek out a low spot.  "If you can safely get noticeably lower than the level of the roadway, leave your car and lie in that area, covering your head with your hands. Do not get under an overpass or bridge. You are safer in a low, flat location." Also be aware that a tornado can be touching the ground and causing damage even if it does not appear to visibly reach the ground. The invisible wind of the tornado is what causes the damage and not the funnel cloud trapped in the tornado.

Topics: safe room, shelter, storm, tornado, underpass, weather