Shortly before 3 p.m. Wednesday afternoon, as temperatures in Butte County hovered around 106 degrees, a man pushed a burning car into a ravine in Chico in what authorities are calling an act of arson.
Within minutes, the flaming vehicle set ablaze tall grass that had sprouted after a rainy winter but had dried out in recent weeks. Soon, oak trees and grapevines began to burn, and wind-blown embers raced down canyons and ridges in the Lassen foothills, carrying new plants with them.
By nightfall, the Park Fire had grown to 5,500 acres, and by the next morning it had grown sevenfold. By Friday, the fire had grown beyond control to 190,000 acres — the largest so far this year in California — with little sign of slowing.
Experts believe the fire’s explosive growth is due to a perfect combination of hot, dry conditions, combustible vegetation and a landscape that hasn’t burned in decades. The isolated terrain has made it difficult for crews to reach the perimeter of the fire, and the fight could be long and arduous as they struggle to gain a foothold.
“This is really the first fire in recent years in California that I would call extraordinary — and that’s not a good thing,” Daniel Swain, a UCLA climate scientist, said at a news briefing. “This fire is huge and it’s done some pretty incredible things.”
Indeed, the fire and its massive smoke plume have already exhibited rare and erratic behavior, including “supercell thunderstorm-like features” with large-scale rotations, Swain said. On Thursday, images captured by AlertCalifornia fire cameras appeared to show the fire spewing tornado-like swirls, sometimes called fire whirls or firenados.
“At this point, the fire is kind of creating its own weather, and it can be pretty unpredictable,” said Courtney Carpenter, a meteorologist with the National Weather Service in Sacramento. “Very large, explosive wildfires can create thunderstorms; they can produce swirling plumes of fire that can mimic tornadoes.”
The Park Fire’s thunderstorm characteristics have not yet produced lightning, though Carpenter said that’s still possible given its “explosive growth” and extreme behavior. She noted that smoke from the fire has already reached Oregon.
Fortunately, the fire’s rapid spread has so far kept it moving north and east — stretching across northern Butte County and a growing portion of Tehama County — in a relatively isolated mix of grass, brush and woods, far from the threatened communities of Cohasset and Forest Ranch. But Swain said it’s almost certain it will grow several times larger than it is now, and likely spread to several hundred thousand acres before it’s contained.
“This is a fire that’s going to haunt us for weeks, if not months,” he said. “It could be one of those fires that starts in mid-summer and burns into mid-fall … and could end up being a bigger threat to communities down the road.”
The fire has already left a trail of destruction. Garrett Sjolund, chief of the Butte County unit of the California Department of Forestry and Fire Protection, said “numerous structures” have been burned, with 134 buildings destroyed and 4,000 others threatened.
Ignited within the Chico city limits, the fire followed an extremely favorable trajectory, experts said, driven by dry southerly winds that carried it away from the city center.
Authorities, however, have been concerned about the fate of the Cohasset community, where they initially feared a repeat of the 2018 Camp Fire, which leveled the neighboring community of Paradise and killed 85 people — California’s deadliest wildfire ever recorded. During that fire, dozens of people were stranded on the area’s limited roads as they tried to escape.
“Cohasset was of particular concern to us because … there’s only one way out: a narrow, winding road,” Butte County Sheriff Kory Honea said. “It’s difficult to get through, so we wanted to get these warnings out as quickly as possible.”
About 4,000 residents were evacuated from Cohasset, Forest Ranch and parts of northeast Chico, as well as several rural areas in southern Tehama County.
While the dry winds that spark fires in the region typically come from the north, a less frequent pattern brought them from the south this week and sucked up all the moisture from the San Francisco Bay Area that they usually carry with them, said Carpenter, the weather service meteorologist.
“The weather has been very dry over the last month – and hot – and that’s why we’re seeing these critical fire conditions,” she said.
The area was placed under a red flag warning, signaling dangerous weather conditions that could promote rapid fire growth, on Thursday and Friday.
This pattern spread the flames into wilderness areas that had not been touched by fire in decades or more, making them more abundant with thicker vegetation and dead and dying brush, which ignites easily and quickly.
“There are huge amounts of live and dead fuels,” said Dan Collins, a spokesman for Cal Fire’s Butte unit. He added that the Ishi Wilderness and parts of Cohasset “have no history of fires” to date.
The region’s rugged topography hampers firefighting efforts, with steep cliffs, vast canyons and few roads through the national forest.
“That’s one of the big challenges, just getting people [to the fire lines] “Because of the remoteness of the area,” Collins said.
The blaze isn’t the only one causing concern in the West. Cal Fire is battling more than 20 active fires in the state, while crews in Canada are battling a 36,000-hectare wildfire in Alberta province that has already razed parts of the historic resort town of Jasper. Experts say many of the fires have been fueled by the persistent, record-breaking heat wave that has blanketed the West for weeks.
Chico area residents are anxiously watching the park fire’s movements.
“It’s been a pretty turbulent time for us,” said Don Hankins, a professor of geography and planning at Cal State Chico who also serves on the Butte County Fire Safe Council.
The Big Chico Creek Ecological Reserve, where he conducts much of his research, has already burned, and cameras indicate that nearly all of its infrastructure has been lost, including a barn dating to the 1870s, Hankins said.
While the fire has some echoes of the Camp Fire, the Cohasset community has prepared for a potential fire in recent years, Hankins said, including fuel reduction projects and prescribed burns to help remove some of the combustible material that lies between the town and the wilderness.
“But unfortunately, with the wind that’s blowing and the scale of these projects, it’s not necessarily enough to make a difference” if the fire continues to burn out of control, he said.
In the coming days and weeks, more and more area is likely to be affected by the fire as crews contend with rugged volcanic topography and persistent hot, dry conditions.
“It’s unlikely that the fire will be easily controlled,” Hankins said. “We have a long season ahead of us before the rainy season comes, and that will really be the ultimate solution to the fires that are happening in the West right now.”
Sjolund, the Butte County fire chief, said he hopes an expected drop in temperatures and increase in humidity this weekend could help fight the Park Fire — and others throughout the region.
“It’s a moving target because of the way the weather is changing,” he said. “This fire is spreading very quickly.”
