A brush fire in California formed a smoke "tornado"! Watch:
Smoke-nadoes are created in a very similar manner to dust devils. The fire creating the smoke is MUCH hotter than the surrounding area, so the air over the fire rises very fast. The air around the fire is much cooler and will likely be either sinking or not rising as fast as the air over the fire. This effect is called differential heating and is the exact reason we get dust devils. The differential heating causes a horizontal roll to develop on the edge of the fire. If this horizontal roll is pushed by wind over the fire, then it will tilt vertical and form these smoke-nadoes. That process can also form a fire-nado where it looks like a tornado is made of fire with flames climbing up the rotating column of air.Â
