Tornado caused by wind and cold air comes face-to-face with each other and the wind to cause rotation. And when the whirlwind-level causes the end side down, touch the ground causing a tornado.
Tornadoes occur from hot air and cold air meet and form a whirlwind. And when the wind is not constant. Make one end down to touch the ground, causing a tornado.
The tornado caused by hot air and the cold wind to meet the formation cause and the whirlwind. And when the wind rotate the level is not constant. The end of one side down a floor causing a tornado.