Question

Tornadoes are common in area's of the flat plains because ?

Answer 1

When there is a mixture of warm and cool air it combines which then makes a Tornado, Most Tornadoes happen in the Fall, Summer, and Spring because the temperature fluctuate, from hot to warm to cool to cold in just matter of times and sometimes we may not realize it! 

Answer 2

Flat plains are ground zero for tornadoes. They almost ALWAYS have the perfect conditions for a tornado to take advantage of. In order to form a tornado, warm air has to clash with cold air, each moving in opposite directions. Flat plains are areas without any obstruction, so very often warm air and cold air WILL clash in these types of area's, forming a tornado.