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Tornado Damage

Tornadoes are natural phenomena that may not match the scale of hurricanes or earthquakes but can create intensive damage and devastation in a localized area. They often touch down in unpopulated areas and leave little or no damage, but they can level homes and cause many deaths when they hit a city or town.

  1. The Fujita Scale

    • There are five basic classes of tornadoes, ranging from an F0 to an F5, based on the Fujita Scale. Theodore Fujita was a scientist with the University of Chicago who devised a scale to rate both the power of a tornado and the damage that each classification can cause.

    Types F0-F2

    • The least powerful tornado is F0 and constitutes wind speeds of less than 72 mph. The damage is minimal and can consist of shallow-rooted trees being knocked over and chimney damage. F1 has wind speeds up to 112 mph and can blow moving cars off roads, knock mobile homes off foundations and peel off roof surfaces. F2 has speeds up to 157 mph that can tear off roofs, demolish mobile homes, lift cars and create light-object missiles.

    Types F3-F5

    • An F3 tornado has wind speeds up to 206 mph and can lift and throw cars, uproot trees and overturn trains. F4 tornadoes can generate wind speeds of up to 260 mph and demolish well-built homes, generate large-object missiles and blow away structures with weak foundations. The F5 is the most powerful tornado on the scale, with winds up to 318 mph. The damage can include homes being leveled and swept away, missiles the size of automobiles being thrown more than 100 yards and trees being debarked.

    Features

    • Tornadoes are most commonly spawned from powerful thunderstorms called supercells. Warm and cool air intermingle, creating a rotation in the cloud. These rotations gain momentum until a funnel cloud is formed and a column of spinning air descends to the ground, creating a tornado. The air itself is invisible, but water droplets as well as debris and dust can create the familiar tornado shape.

    Effects

    • Damage from tornadoes is more localized than from other natural phenomena, such as hurricanes. Tornado damage is localized to a radius around the main funnel. Because a tornado can ascend back into the cloud and descend again, one house can survive completely intact while another a few doors down can be obliterated.

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