While there are many varieties of tornadoes that form, for now we'll just concentrate on two general kinds. The first type of tornado forms in the outflow of a thunderstorm. These tornadoes are generally weak and last for only a short period of time. The second type is the strongest. Rising air inside the thunderstorm updraft tilts the rotating air from horizontal to vertical. This area of rotation, sometimes up to 6 miles wide, is where a tornado is most likely to form.

A tornado, be it large or small, is going to cause damage. When a tornado goes through a town, some houses may be totally demolished while the houses right next door will be untouched. Tornadoes are ranked on the Fujita Scale. The least damaging tornado an F0 on the scale and the most devastating an F5 on the scale.