Aug. 03 -- REDDING, CA -- As authorities sifted the rubble from the fire that burned more than 1,000 residences in Shasta County, they were startled by what they encountered.
A soaring transmission tower was tipped over. Tiles were torn off the roofs of homes. Massive trees were uprooted. Vehicles were moved. In one spot, a fence post was bent around a tree with the bark on one side sheared off.
This was not typical wildfire damage. Rather, it was strong evidence of a giant, powerful, spinning vortex that accompanied the Carr fire on July 26. The tornado-like condition, lasting an hour and a half and fueled by extreme heat and intensely dry brush as California heats up to record levels, was captured in dramatic videos that have come to symbolize the destructive power of what is now California’s sixth-most destructive fire.
It may take years before scientists come to a consensus on what to exactly call this vortex — a fire whirl, as named by the National Weather Service, or a fire tornado. Whatever it’s called, it’s exceptionally rare to see a well-documented fire-fueled vortex leap out of a wildfire and enter a populated area with such size, power and duration.
It’s believed to have lasted from 7 p.m. to 8:30 p.m. on July 26 and struck some of the hardest-hit neighborhoods in Redding.
This kind of fire twister has been documented before, but only a handful “at this sort of scale,” said Neil Lareau, assistant professor of atmospheric sciences at the University of Nevada, Reno, who was among those comfortable calling it a fire tornado. “You’re starting with a rare event to begin with, and for it to actually impact a populated area makes it even rarer.”
The National Weather Service on Thursday said a preliminary estimate of maximum wind speeds in the vortex were in excess of 143 mph. That would make it equivalent to a twister with a rating of EF-3 out of a maximum of 5 on the Enhanced Fujita scale.
“Depending on the final number, this might actually be the strongest ‘tornado’ in California history, even if it wasn’t formally a tornado,” UCLA climate scientist Daniel Swain said by email. There have been a couple of marginal EF-3 twisters in California’s past, “but this fire whirl was almost certainly longer-lived, larger in spatial scope and perhaps even stronger from a wind speed perspective.”
It’s too early to say whether the vortex contributed to the deadly ferocity of this blaze, which killed six. But with climate change playing a factor as California enters a worsening era of wildland fires, last week’s fire vortex adds a layer of unpredictability and danger.
“Not all big fires are going to result in these big fire whirls, even in a future that’s much hotter and drier,” Swain said. “This won’t be the primary risk associated with wildfire ever. But under the right atmospheric conditions, all else being equal, the increasing intensity of fires themselves will play a role in producing these localized fire weather conditions that can be quite extreme.”
Radar analyzed by Lareau clearly shows a spinning vortex in northwest Redding as the Carr fire rapidly expanded in the evening of July 26.
Lareau roughly estimated the vortex as being as perhaps 500 yards in diameter at its base before possibly contracting. “It’s covering blocks,” he said.
“It was definitely a massive one, and that just speaks to how intense the heating was,” said National Weather Service meteorologist Mike Kochasic. “It created such a massive whirl that it looked like a tornado … and it takes an impressive amount of heating and local wind swirling up to create something like that. It was quite a monster.”
It’s possible for fire vortexes to “move fairly quick out in front of the main line of the fire — it can spread a little bit quicker compared to the main fire,” Kochasic said.
Wind damage was also reported in areas untouched by flames.
A team of officials led by the California Department of Forestry and Fire Protection is looking into the vortex as part of its investigation of the blaze.
This vortex is dramatically different from the garden-variety whirls that have been more of a curiosity in past fires, which are more like dust devils in terms of scale, rising for perhaps two stories and lasting for less than 10 minutes.
Lareau’s radar data show that one of the worst-hit areas was on Quartz Hill Road, around a Y-shaped junction of electric transmission lines — a matter of hundreds of feet from where Melody Bledsoe, 70, and her great-grandchildren, Emily, 4, and James Roberts, 5, died as the fire swept through their home.
Half a mile west from the Bledsoes’ home is Lake Keswick Estates, where Justin Sanchez, 37, fled in the back of a pickup truck with irreplaceable photos lining its bed, as his father, Greg, 69, drove them away from what he called a fire tornado.
“Oh my gosh! Oh my God!” Sanchez wailed as he sought to record what he expected would be the last few moments of his neighborhood before his home burned. His phone camera captures a giant vertical, cone-shaped cloud — appearing with an orange glow at the base — spinning counterclockwise. Flames can be seen in the foreground.
“It was like the movie ‘Twister,’” Sanchez said in a telephone interview. “It was a massive, massive, huge tornado. … It was spinning so slow on the outside, but there were heavy, massive pieces of shrapnel just floating around with the fire.”
Sanchez said he could see the blaze earlier that day, but it wasn’t traveling particularly fast. Then he heard his neighbor shout, “It just jumped the river! It’s headed our way!”
“Within a matter of 10 minutes there, once the ‘fire-nado’ started almost inching on our neighborhood, the winds had to have been 40 to 60 mph winds … the sky got dark,” Sanchez. “I didn’t understand how a fire and tornado could combine into one massive death machine.”
He said he dashed into the house a couple of times to grab some photos, but the second time he came out, the fire had come probably within a football field away. Sanchez said the vortex traveled three to four miles in just 15 minutes.
A late gust was so intense that the last keepsakes he nabbed were blown out of his arms.
“I knew everything was going to become lost, and it was going to end up killing people on the way. It was nothing like I’ve ever seen or heard of in my life,” he said.
As Redding Police Chief Roger Moore evacuated residents from the River Ridge neighborhood east of the Sacramento River, he watched the growing flames and smoke plume approach the western bank of the Sacramento River, hop over it, grow, then come together as what he called a “plume tornado.”
Trees appeared to be levitating, and branches and sheet-metal roofs seemed to orbit the column, Moore said. Uprooted objects were launched into the air and ignited mid-flight. Vegetation and homes hundreds of feet from the column caught fire before the twister arrived, he said. It was as loud as a roaring jet engine.
“Wherever the center of the tornado went, it decimated it. You’re looking at this whole column of fire, and it’s just monstrous,” Moore said. The swirl of fire and smoke destroyed sections of the Stanford Manor community. “The only things left standing were the homes on the edges. Some would ignite; some would remain standing.
“I don’t know how fast that tornado was moving, but it was probably faster than a human can run,” Moore said.
Spinning vortexes of fire can be deadly, whether they’re called a fire tornado or a fire whirl. What’s common in both is that they are driven by an exceptional amount of heat being released into the air — heat probably fueled by record or near-record vegetation dryness caused by the state’s persistently high temperatures.
Other factors are important, though, said Craig Clements, an associate professor and director of the Fire Weather Research Laboratory at San Jose State University.
“It’s really too early to tell what caused it, and there still needs to be a lot of scientific investigation.”
The rising heat can reach speeds of up to 130 mph, Lareau said, send smoke up beyond its normal limit of about 15,000 feet and form its own fire-fueled cumulus cloud, rising to as high as 39,000 feet. The creation of the puffy cloud means that more heat is being dumped into the column of hot, rising air. That air is replaced by winds rushing in all around the chimney of rising air.
The lowest part of the vortex often takes an orange glow from combusting gases rising within its core, according to a 2012 study by the U.S. Forest Service.
Fire whirls can range from less than 4 feet to as large as 1.9 miles in diameter, the study said, and can be especially hazardous by increasing fire intensity, triggering spot fires from burning debris floating from the vortex, and causing an unpredictable mix in the speed and direction of the fire.
In 2008, a whirl caught firefighters by surprise in the remote Indians fire that burned in extremely dry chaparral in the Los Padres National Forest, causing serious injuries and forcing the deployment of fire shelters.
Lin reported from San Francisco, Serna from Los Angeles and Sahagun from Redding.
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