All About The Natural Phenomenon Of Fire Whirls

While a spinning vortex of fire dancing on the horizon looks mesmerizing and Instagram-worthy, it can also be dangerous. These twirling columns of fire are called fire whirls, and they aren't common occurrences during fires. They appear when the right amount of wind and fire combine, forming a column of fire that resembles a mini-tornado (via National Wildfire Coordinating Group.)

Fire whirls are also called firenadoes, fire tornadoes, and fire devils. These naturally occur as gasses and hot air rise from a fire, per USDA Forest Service. When the gasses rise, it may also bring with it some ashes, debris, and flames, causing the whirling vortex to catch fire and form the whirling effect. Fire whirls come in different sizes, some being as small as a foot while others can be as massive as 500 feet in diameter given the right conditions. And although they are sometimes called fire tornadoes, they aren't tornadoes in the strictest sense since they are induced by hot temperatures as opposed to air pressure.

When does a fire whirl form?

Fire whirls typically arise during wildfires and firestorms, but they are not so common. In order for the fire whirl to be formed, an updraft must be present and combined with flames. However, even a bonfire can form a small fire whirl. According to Skybrary, a massive fire whirl can reach up to 1,090 degrees Celsius, or nearly 2,000 degrees Fahrenheit. While most fire whirls only last a few minutes, bigger ones can have a duration of 20 minutes and wind speeds of 120 mph. This is when the fire becomes a danger as it can cause massive damage to areas, especially when there are flammable materials in the path of the fire whirl.

The behaviors and structures of fire whirls have also been studied in a laboratory setting to better understand the natural phenomenon. Ultimately, per Annual Reviews, the study focused on the temperature, velocity, and vorticity to answer questions about the nature of fire whirls.