Common Tornado Myths

Illustrated tornado from the book The Wizard of Oz © W. R. Wright, Piglet Press Inc. (www.halcyon.com/piglet/) Has someone told you to open your windows during a tornado? Or has someone told you that you don't have to worry about tornadoes because the place where you live is protected? These are two of the most common myths about tornadoes. Neither of them are true. Scientists once thought that the low pressure in a tornado caused the normal air pressure in houses to explode out. It turned out that the strong winds from the tornado destroyed the houses, not the pressure change. In fact, opening the windows can cause even more damage. Some people thought that tornadoes couldn't cross mountains or rivers. This is true for small tornadoes, but the strong ones can. And they're the ones that cause the most destruction.

Common Tornado Myths

Illustrated tornado from the book The Wizard of Oz © W. R. Wright, Piglet Press Inc. (www.halcyon.com/piglet/) Has someone ever told you to open your windows during a tornado? Or has someone ever told you that you don't have to worry about tornadoes because the place where you live is protected? These are two of the most common myths about tornadoes and neither of them are true. Scientists once thought houses exploded when a tornado passed over because of the really low pressure in the tornado. They figured that the higher pressure in the house would knock down the walls trying to get out. So they said you should open your windows to equalize the pressure. It turns out that more damage can be done by opening the windows. Some people thought that tornadoes couldn't cross mountains or rivers. This is true for small tornadoes, but the strong ones--the ones which cause the most destruction--can cross almost anything.

Common Tornado Myths

Illustrated tornado from the book The Wizard of Oz © W. R. Wright, Piglet Press Inc. (www.halcyon.com/piglet/) Scientists once thought that you should open your windows during a tornado so your house won't explode. The thinking behind this idea is that the extreme low pressure in a tornado would cause the air in your house to explode. Opening your windows would let the air expand without damaging your house. As it turns out, houses aren't as sealed as they thought so the air would have no problem getting out. It turns out that the strong winds associated with a tornado can lift the roof off a house. Without the support of the roof, the wall are blown down and they fall outward. The roof may be dropped back on the rubble or some place nearby. This gives the impression that the house exploded. Another common myth was that places were "protected" by a mountain or a river. In reality, no place is safe. While weak tornadoes may not be able to crest mountains or jump rivers, the strong ones can. Another problem is the infrequentness with which tornadoes occur. People in a town can draw a conclusion that since no tornadoes have ever come through the town but a couple have happened right outside of town, then they must be protected. The topic here is not protection; it's probability. A town is small while the surrounding countryside "outside of town" is large. Chances are that a tornado would strike in the larger area rather than the smaller one. This can be a problem because people won't take shelter if they think they're already safe.

Last modified prior to September, 2000 by the Windows Team

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