Indoor tornado's? are they possible?

Question

From what I understand tornado's are formed from hot and cold air colliding. Should I be concerned about turning my heater on to quickly on a cold morning. Or blasting the AC suddenly on a hot day. I think a small tornado inside of my car could cause a crash or something.

Answer 1

Not the way you are worried about but here's some guys that made one indoors

http://www.engadget.com/2007/10/27/merce...

Answer 2

Actually, tornadoes are not caused simply by the collision of warm and cold air masses.  When that happens you get a front which in turn could produce storms if other factors are right.  Tornadoes are caused mostly by an effect called wind shear, where winds change speed and direction as altitude increases.  This shear can induce a sort of horizontal roll which, if a storm passes over the roll, can tilt the roll upward and vertically in the storm updraft.  Now you have a rather broad vertical rolling motion, and on occasion areas of the vertical roll contract and increase the speed of rotation, producing a tornado.  

Cold and warm air masses collide fairly often, but tornadoes are actually rather rare, given the amount of storms that do occur.  

Answer 3

would that be the tornado in youre head