A fire tornado or fire devil, better known as fire whirl, is a phenomenon in which a fire, under certain air temperature and current conditions, acquires a vortical motion and forms a whirl, or a tornado-like vertical rotating column of air. 

Most of the largest fire tornadoes are spawned by wildfires. It may be whirlwinds separated from the flames, either within the burning area or outside it. Or it may be a whirling mass of flame itself that draws everything toward its center. It can also abet the ability of wildfires to propagate and start new fires.

A fire tornado is usually 10 to 50 meters high and a few meters wide, and lasts for only a few minutes. However, some can be  frighteningly tall, reaching heights of about a kilometer, with center winds of over 160 kph, and persist for more than 20 minutes.

Fire tornadoes can also be generated by other natural events such as earthquakes and thunderstorms, and can be incredibly dangerous, in some cases spinning well out of the zone of a fire itself to cause devastation and death in a radius not even reached by heat or flame.

The 1923 Great Kanto earthquake in Japan which ignited a large firestorm, spawned a huge 15-minute fire tornado that claimed 38,000 lives in the Hifukusho-Ato region of Tokyo.

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