California "firenados" There are spectacular rotating towers of fire that can be seen in recent television images of fire in California. In this video, we see that these fire towers can rotate either clockwise or counter clockwise.
What is the mechanism behind these "firenados?"
 A: Also known as a fire whirl or a fire devil. 

The thermal turbulence around fire causes heated swirls to form (in any rotation) and as oxygen moves up the column it lifts the flames up.  As the air rises, it continues to rotate, drawing in more air and slowly drawing the flames upward in a tight spiral. Most fire whirls stay small -- a foot or two in diameter. But some can grow to be 400 feet (122 meters) tall and 50 feet (15 meters) wide.  Usually they are perpendicular 
Not every vortex begins standing straight up. Some begin with the axis of rotation oriented parallel to the ground. Then, an uplifting force tilts the horizontal vortex up until it stands on one end. Many Scientists now believe that this is how many fire whirls form. They also think the same processes explain how the vortex at the heart of a supercell tornado -- the mesocyclone -- develops and evolves.
Here's a video of how to make a fire whirl in your own back yard.  The metal screen causes the column of air to rotate as well and draws the flames upwards.
