A tornado is a violently swirling column of air that forms at the base of a thunderstorm. When the tornado is visible, it's because the air gathered up water droplets, dust particles and debris. It is a destructive force of nature, with winds that can exceed 300 miles per hour, and it can damage areas as large as a mile wide and 50 miles long.Continue Reading
Tornado formation isn't well understood. The most powerful ones form from supercells, which are thunderstorms with frequent lightning, heavy hail, flash floods and severe winds. There are several types of tornadoes, including waterspouts, landspouts and multiple-vortex tornadoes.
A landspout starts over land in arid climates in the early stages of a tornado. It forms from the ground up to meet the main updraft. It carries mostly dust until condensation from the cloud cover mixes in water.
A waterspout forms over a body of water when instability causes a vortex of swirling air to rise and meet the cumuliform cloud above. It doesn't carry much water up with it; the water is added by cloud condensation later. When it forms in very cold regions under a snow squall, a waterspout is called a snowspout.
The multiple-vortex tornado is comprised of several swirling columns of air and debris inside and around the primary.Learn more about Atmosphere