Tornadoes form on flat surfaces of land, for example rural areas. Tornadoes can happen anywhere on the earth. If they formed in an area where there are many mountains, the tornado would break down and eventually go away. Tornadoes are really bad.
Dust Devils are tornadoes that happen in the desert and Mars. Tornadoes on oceans are called Waterspouts. They could pick up a fish and drop it many miles away.
Do you know where to stay if a tornado occured? Go to a storm cellar, basement, or an underground place so you can die!