Where do tornadoes most likely occur and why?

Question

I need this because i'm in the middle of studying for my science exam. Im a freshman in high school.

Thank you!

Answer 1

They occur most frequently in the United States (they are actually rare outside of the U.S.).  Within the U.S., they occur most frequently in the center of the country in an area known as "Tornado Alley" which stretches from North Texas, across Oklahoma, Kansas, Nebraska, and to the eastern edge of North and South Dakota.

They occur there because the cold dry air from the west pushed along by the jet stream collide with the warm moist air being fed north from the Gulf of Mexico.  This unsteady air creates extreme turbulence, strong thunderstorms and tornadoes.