A tornado is a violently rotating column of air, pendant from a thunderstorm, and in contact with the ground.
Tornadoes come in many sizes, shapes, and colors.
They can range in width from several yards to more than a mile. They can last from a few seconds to several hours. They can move forward at speeds of up to 70 miles per hour, or stand nearly still. Most people recognize the funnel-shaped cloud of a typical tornado, but the funnel can vary considerably in appearance. Some are long and slender while others are wider than they are tall.