Meteorology/Tornadoes

What Are They?
Tornadoes are a whirlwind that forms over land. They are spawned from thunderstorms, most of which are known as supercells. They form mainly over the plains where the cold, dry air of the north, and the warm humid air of the south make contact, forming unstable air. This unstable air creates updrafts, downdrafts, wind shear, and more. This is what creates the conditions for the formation of a tornado.

How Strong Are They?
Tornadoes vary in strength, and of the 1,200 tornadoes (on average) that touch down over America every year, the vast majority are weak, with winds less than 110 mph. Many tornadoes can exceed this, with stronger tornadoes packing winds of 110-165 mph. Only a very small percentage of tornadoes reach that status of violent tornadoes, with winds exceeding 166 mph. The most violent tornadoes have contained winds nearly double this, with the Bridge Creek-Moore tornado of May 3, 1999 being the strongest officially on record, with measured winds of 301 mph.