MOLINE, Ill. — Many places across the U.S. are currently in fire season. During this time, videos of fire tornadoes, also known as firenadoes, sometimes go viral. Although these videos are exhilarating, not every one of them is a true firenado.
In 1978, David W. Goens, a researcher for the National Weather Service in Missoula, classified the different types of fire storms into four groups:
Fire Devils
This phenomenon is the most natural of the four. They are part of fire turbulence with little influence on fire behavior or spread. They are between 3ft to 33ft in length and their rotational velocity gets up to 22 mph.
Fire Whirls
This is made of fire, topographical effects, and other meteorological factors. They play a role in fire spread and behavior and are a notable hazard to firefighters. Fire Whirls are between 33ft to 100ft and have a rotational velocity between 22mph to 67 mph. In viral videos, these are the phenomenon most commonly mistaken for fire tornadoes.
Fire Tornadoes
This is the first example of large-scale fire dynamics. They play a role in fire spread and behavior and are very dangerous for firefighters or anyone else in their path. They are between 100ft to 1,000ft long and have rotational velocities up to 90 mph. Just like an actual tornado, they can uproot trees, snap power poles, and blow away roofs, alongside the danger already posed by fires. They can be seen on radar, just like regular tornadoes.
Fire Storms
This is an extremely rare and highly unlikely weather event. They are extremely violent and destructive storms that can range anywhere from 1,000ft to 10,000ft in length with winds up to 110 mph.
Fire Tornadoes can appear more commonly as wildfires begin to occur more often In 2020, there were three major wildfires in California that each had a firenado. One was so dangerous that the National Weather Service had to issue the first-ever fire tornado warning.
Researchers are working in labs to replicate them and learn more about them. The information we gain from research can help meteorologists with forecasting, allowing them more time to warn the public and ultimately save lives.