Around 12:40 p.m. on July 12, firefighters on the Deer Creek Fire, east of Moab, Utah, realized the flames they battled burned even hotter, higher and faster than before. The crews were spread out around the blaze, trying to box it in; it had been intense, running six miles in its first five hours. The weather had been hot and windy, sure, but this voracious fire behavior was new. The sky glowed a deep red as the flames grew to 250 to 300 feet. Leaders began radioing their crews, telling them to move farther away to safety.
And then, the fire and its inky black smoke column began to rotate.
A wildfire rarely creates its own tornado, or pyro-vortex. (Fire whirls, a fire tornado’s little brother, are more common and are smaller, briefer and less intense.) Two key ingredients must first be present: an especially hot fire, and something to set it spinning.
Gusts coming off the flanks of the La Sal Mountains provided the spin for the Deer Creek Fire’s tornado. Here, wind flows over the mountains like a river flowing over rocks. The mountains disrupt the wind much like a rock disturbs a river, creating an eddy of swirling water — or, in this case, air. “The fire was burning inside one of these big wake eddies coming off the La Sal Mountains,” said Neil Lareau, a professor of atmospheric science at the University of Nevada, Reno. “And that set the stage.”
The pyro-vortex began sucking debris, plants and anything in sight into its path. The National Weather Service later dubbed the fire tornado “significant,” with winds between 111 and 135 mph. This level of tornado, officially an “EF2 Vortex,” damages buildings, uproots trees and can overturn vehicles.
Fire tornadoes of this magnitude happen once every couple of years. The Carr Fire’s tornado in 2018 killed two firefighters and injured several others, and other fire tornadoes were recorded in the U.S. in 2020 and 2021. But there is little useful data on their occurrence, Lareau said, and no serious research into whether they’re increasing as the climate warms.
But there is plenty of evidence that high-intensity fires, a key component of fire tornados, are happening more often. One study last year found that intense wildfires are twice as common now as they were two decades ago. “They go hand-in-hand,” Lareau said.
As the pyro-vortex on the Deer Creek Fire spun up, some firefighters began to seek shelter outside its path. But others were directly in its way. Fires create their own powerful updrafts, which, in turn, concentrate the flames’ rotation. It’s like a figure skater who starts rotating slowly, pulls their arms in and then starts spinning faster: A fire’s column of hot rising air can do the same — concentrating the whirling motion and strengthening the tornado.
As the tornado swirled across a sagebrush field, it ripped the roof off a house, yanked a heavy gate out of the ground and tossed it skyward. Two hotshot crews, hunkered down in an already burned area to the east, were blasted in the face with ash and debris. Another crew sheltering to the south described being in the middle of an “ash dust storm,” unable to see more than a couple feet in front of them.
Some fire engines had time to escape, down a road. But the captain of what would have been the last engine out was concerned about getting stuck in the back of traffic. Firefighters considered their options over radios. “I don’t know if anyone’s got time at this point,” one said.
Above them, the fire’s updrafts of hot air were triggering a thunderstorm, making the tornado even stronger and more ferocious. When millions of water droplets condense, they dump heat back into the atmosphere. In turn, that heat reinvigorates the column of hot rising air coming off the fire — further stretching and intensifying the tornado.
“All right, fellas, everybody’s gotta get ready for it to get hairy,” someone inside the cab of the remaining engine said. “There’s going to be fire everywhere,” the captain seemed to say, telling the crew to stay near the truck and defend structures if possible.
By 1:09 p.m., less than 30 minutes after the tornado formed, it reached the engine. And then it stalled out, and a nearby structure immediately caught fire. “The engine was near the center of the tornado surrounded in a cyclone of hot embers, ash and debris which intensified as the structure next to them burned,” a “rapid lesson sharing” review of the incident stated.
Sheet metal, roofing material, trees and other debris flew through the air, narrowly missing the engine. The winds lifted a large shipping container and carried it hundreds of feet away before dropping it not far from the firefighters’ vehicle. The only thing that could seen through the windshield was millions of flying orange embers.
Five minutes later, almost as quickly as it began, the tornado petered out. “I’ve been in fire for 31 years, and I have never seen anything strong enough to rip a roof of a house,” one hotshot superintendent told the authors of the incident report. Somehow, no one was injured. “This really seems like a near miss,” Lareau, who categorized the tornado as “extremely violent,” said. “The fact that no one was injured is a testament to good decision making,” the incident report concluded.
“The fact that no one was injured is a testament to good decision making.”
Still, the close call offered lessons for crews facing similar situations in the future. There had been signs the day before that the fire was getting more intense, for example. There was a fire whirl, which hinted at the eddying winds. And the firefighters had to struggle to communicate once the tornado approached them and radio channels became overloaded. Where exactly everyone was became unclear, making it hard to get the firefighters to safety.
The Deer Creek Fire kept burning, and the firefighters kept fighting it. As of Aug. 11, the fire was 100% contained, after burning nearly 18,000 acres.
Fires burn near mountains all the time in the West, but not every fire near the mountains is vulnerable to a fire tornado. The La Sals’ isolated nature makes them unique, with wind able to flow around both sides of the range. “But it is definitely the case that the lee side of mountain ranges is a location prone to this sort of fire behavior,” Lareau said. Local forecast offices and incident meteorologists who know the terrain and weather partners intimately are the first line of defense, he added; they have the best chance of predicting when these situations could occur and should keep an eye out.
Fire tornados can be deadly. But they’re also a reminder of how dynamic and powerful fires are, with the ability to weave extreme heat into their flames and create their own weather. “They’re spectacular,” Lareau said. “They’re an amazing system to watch.”
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