The winds of a tornado are the most violent winds that occur on the earth, reaching speeds of up to 300 mph. Tornados generally rotate counterclockwise in the northern hemisphere, and clockwise in the southern hemisphere. It is very rare to find a tornado which rotates in the wrong direction. Most tornadoes also follow a northeast course at about 10 to 20 mph. Tornadoes usually last less than an hour, traveling distances of about 20 miles.
Tornadoes occur throughout the world, but mostly in the United States.
This diagram shows the number of tornadoes which form throughout the world. The season in which most occur is the Spring and early Summer. The Midwest is an area which is usually hard hit by tornadoes. This area is known as Tornado Alley, because of the number of tornadoes which strike the area each year. One of the most important things to know about a tornado is that they are very dangerous.