Fire tornado

A fire tornado, also called a fire whirl or firenado, is a rotating column of hot air, flame, ash, and debris associated with intense fires such as wildfires and firestorms.

A fire tornado, also called a fire whirl or firenado, is a rotating column of hot air, flame, ash, and debris associated with intense fires such as wildfires and firestorms. It is not always a true tornado in the meteorological sense; many sources describe it as a fire-driven whirlwind rather than a classic tornado. These events are rare but can intensify fire spread and create extreme local hazards.

Definition and terminology

A fire tornado is known by several alternative names, including fire whirl, firenado, fire devil, and fire twister. The term 'tornado' is used inconsistently; some scientists reserve it for a stricter meteorological meaning, while others apply it broadly to any rotating column of air. This phenomenon is characterized by a rotating column of hot air, flame, ash, and debris generated by intense fire conditions.

Formation

Fire tornadoes form when intense heat from a wildfire or firestorm creates rising air, which can begin to rotate when influenced by wind shear and turbulence. The resulting vortex can pull in flaming debris and combustible gases, sustaining and intensifying the rotation. This process is driven by the combination of extreme heat and atmospheric conditions.

Characteristics and behaviour

Fire whirls typically have a visible flame core surrounded by a rotating column of superheated air. Reported temperatures inside fire whirls can reach about 1,090°C (2,000°F). Their lifespan may range from minutes to longer in some cases, and they can loft embers, smoke, ash, and burning debris, increasing the danger and fire spread.

Hazards and fire behaviour

Fire tornadoes can worsen wildfire intensity by spreading embers and flames. They are dangerous because they combine extreme heat with unpredictable wind and debris movement. These events can intensify fire spread and create extreme local hazards, including rapid fire spread and flying embers and debris.

Scientific classification

There is an ongoing terminology debate over whether fire tornadoes are true tornadoes or fire-driven whirlwinds. Many experts distinguish fire tornadoes from true atmospheric tornadoes, and most fire tornadoes are not tornadoes in the strict sense. Sources differ, but several state that these phenomena are fire-driven whirlwinds rather than classic tornadoes.