During a hurricane or cyclone, vortices of air are formed at some points and are very fast. Two whirlwinds of air, one on the ground and the other in the sky, may meet each other at opposite points.
When they unite, they form a frightful structure revolving with a speed of 200 km/hr moving in the direction of the wind.
Tornadoes, carry away objects, root up trees, causing death of many people and animals. Enormous damages are caused by these tornadoes and they can be extremely dangerous leading to casualties.
Below Tornado info from Wikipedia (Read More):-
A tornado is a violent, dangerous, rotating column of air which is in contact with both the surface of the earth and a cumulonimbus cloud or, in rare cases, the base of a cumulus cloud. Tornadoes come in many sizes but are typically in the form of a visible condensation funnel, whose narrow end touches the earth and is often encircled by a cloud of debris and dust.
Most tornadoes have wind speeds between 40 mph (64 km/h) and 110 mph (177 km/h), are approximately 250 feet (75 m) across, and travel a few miles (several kilometers) before dissipating. Some attain wind speeds of more than 300 mph (480 km/h), stretch more than a mile (1.6 km) across, and stay on the ground for dozens of miles (more than 100 km).
http://en.wikipedia.org/wiki/Tornado
