The Dixie fire burning in Butte and Plumas counties mushroomed to more than 100,000 acres Thursday, becoming the second California blaze this year to surpass the megafire milestone.
The aggressive fire has now destroyed at least eight structures, the California Department of Forestry and Fire Protection said, and at least 1,500 more are threatened as it continues its slow crawl east toward Lake Almanor.
The fire was at 103,910 acres and 17% containment Thursday morning, Cal Fire said.
It is the second megafire in the state this year. Days ago, the 105,000-acre Sugar fire in Butte County garnered the designation, for a fire surpassing 100,000 acres.
Wildfire experts have said California’s fires are burning faster and arriving earlier this year because heat and drought have dried the landscape and primed vegetation to burn.
Wind and topography also played a role in the Dixie fire’s latest run, said Cal Fire Butte County spokesman Rick Carhart, as the area’s valleys, peaks and canyons are enabling erratic movement and spread.
“There are fingers of fire that are burning, so it’s not the whole fire front moving together,” Carhart said. “With more flame-front out there, there’s more ability for it to grow.”
Carhart said clear skies in the forecast for Thursday afternoon would encourage fire activity because it “allows more sun onto the fire and heats things up.”
An additional 500 personnel have arrived to help fight the flames, bringing the total size of the crew to just over 3,900, he said. Firefighters have come from Colorado, New Mexico, Arizona and even Florida to help with the operation.
Evacuation orders for Lake Almanor’s west shore, as well as portions of Butte and Plumas County, remain in effect, officials said.
Evacuation warnings have also been issued in Butterfly Valley, the Round Valley Reservoir and Long Valley, the Chester area and the Lake Almanor Peninsula.
Several road closures are in place, including portions of Bucks Lake Road and Highway 89, according to the California Department of Transportation.
During a community briefing Wednesday evening, Cal Fire operations chief Tony Brownell said crews were contending with 40-foot flame lengths, noting that spot fires were increasingly jumping containment lines.
“If conditions hold, we’ve got a great probability of success up here,” he said, but “Mother Nature gets a vote. If the wind comes back up, we get spots over the line.”
Conditions are similarly challenging at the Tamarack fire in Humboldt-Toiyabe National Forest, which swelled across the California-Nevada state line for the first time Wednesday afternoon.
By Thursday morning, the fire was 50,129 acres and only 4% contained, according to the U.S. Forest Service.
Fire incident spokeswoman Tracy LeClair said the focus Thursday remains near the junction of Highways 88 and 89, as well as along Highway 395, where the fire is most active and poses a potential threat to the communities of Spring Valley and Holbrook Highlands.
More than 1,200 personnel are working to quench the flames, she said, including ground crews, helicopters and air tankers.
As with the Dixie fire, firefighters are contending with difficult conditions, LeClair said, including pyrocumulonimbus clouds and fire whirls, which can force them to back off.
“Across the fire, it’s really very hot, dry and windy,” she said, “and on the east side — because of the change in fuels down to piñon, sage and grasses — it’s been very fast-moving and very dangerous.”
Smoke continues to be a problem, with conditions in nearby Markleeville moving into the “very unhealthy” range Thursday morning, according to EPA air monitoring site AirNow.gov.
The Tamarack and Dixie fires, as well as the massive Bootleg fire in Oregon, are creating such large plumes that their smoke has made it to the East Coast.
The Alpine county Sheriff’s Office ordered mandatory evacuations for the Blue Lakes Road area and the Mesa Vista area. Previously issued evacuation orders in Markleeville, Grover Hot Springs, Shay Creek, Woodfords and nearby areas remain in effect.
The Douglas County Sheriff’s Office in Nevada has issued voluntary evacuations for all residents in the Topaz Ranch Estates and Topaz Lake areas. Previously issued evacuation warnings in the Leviathan and Holbrook Junction areas are unchanged.
Portions of Highway 88 remained closed Thursday because of the fire, Cal Trans said.
Highway 395 is now closed from China Springs Road to the Nevada-California state line.