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Tornado means to turn in Latin. A tornado is a violent whirling wind, characteristically accompanied by a funnel-shaped cloud extending down from a cumulonimbus cloud. Commonly known as a twister or cyclone, a tornado can be a few meters to about a kilometer wide ....

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.... the passage of fronts. They develop within low-pressure areas of high winds; the speed of the funnel winds themselves is often placed at more than 480 km/hr (more than 300 mph), although speeds of more than 800 km/hr (500 mph) have been estimated for extremely strong storms. Damage to property hit by a tornado results both from these winds and from the extremely reduced pressure in the center of the funnel, which causes structures to explode when they are not sufficiently ventilated to adjust rapidly to the pressure difference. The pressure reduction is in keeping with Bernoulli's principle, which states that pressure is reduced as velocity increase ....