Several grass fires burned parts of North Texas Monday. A combination of low humidity, dormant vegetation and strong winds were to blame for the fires.
Texas Sky Ranger captured the leading edge of one of the fires, which included a fire vortex that resembled a tornado of fire.
This vortex is caused by rapidly rising air that has been super-heated by the fire. As the air rises, it draws the flames briefly higher.
The rotation of the flames is a function of the rising air combined with gusty winds.
The whole thing lasts only a few seconds. Other than looking like a tornado of fire, the fire vortex shares very little in common with actual tornadoes.