What Is a Tornado?
A tornado is a great whirling windstorm. Tornadoes start in muggy thunderstorm weather, when hot, moist air meets cold, dry air. The heavier, cold air sinks, and the warm air rises quickly from the ground. The winds whirl and twist into a dark, funnel-shaped cloud, or in a slender rope-like form that reaches the ground.
Some have a churning, smoky look to them, and other contain “multiple vortices”, which are small, individual tornadoes rotating around a common center. Even others may be nearly invisible, with only swirling dust or debris at ground levels as the only indication of the tornado’s presence.
The whirling wind of a tornado can spin around at more than 250 mph. The furiously spinning funnel sucks up dirt and debris. Large tornadoes are so powerful that they can pick up cars and flatten buildings. Tornadoes usually last less than an hour. Damage paths can be in excess of one mile wide to 50 miles long.