A sign in South Lake Tahoe warns of very high fire danger
Highway 50 remained closed due to the Caldor fire as smoke and ash fill the air in the Lake Tahoe Basin.
(Jason Armond / Los Angeles Times)

All-out fight to save South Lake Tahoe as Caldor fire forces evacuation warnings

The Caldor fire has swelled past 143,000 acres and continues to burn toward South Lake Tahoe, where evacuation warnings have people on high alert. The blaze was only 12% contained as of Friday morning.

Fueled by low humidity and gusty winds, the Caldor fire Friday morning continued to close in on South Lake Tahoe, where the threat of the fire has triggered evacuation warnings and sent vacationers packing as toxic smoke converges over the region.

Much of the growth in the past 24 hours occurred along the northeastern portion of the blaze — directly toward the southern end of the Lake Tahoe Basin — where the fire raced rapidly up steep terrain and began torching treetops, fire officials said.

Fire officials on Thursday said the flames were only 14 miles from reaching South Lake Tahoe. Capt. Stephen Horner, a public information officer for the fire, said it “did advance a little bit closer,” by Friday morning. After igniting nearly two weeks ago, the fire has surged past 143,000 acres and is only 12% contained.

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With the blaze nearing the popular vacation destination, fire officials have scrambled to protect it.

As the blaze advanced Thursday, fire and law enforcement officials issued evacuation warnings for communities within the southern end of the Tahoe Basin. South Lake Tahoe city officials declared a local emergency and the Lake Tahoe Visitors Authority advised visitors to postpone travel plans. Smoke from the Caldor and other large areas fires has choked the region for days, leaving residents and vacationers to contend with blackened skies and toxic air.

Many have already left town, leaving what’s typically a bustling Labor Day vacation haven eerily empty. Others have shut their windows and doors tight, to keep out harmful particulate matter in the air. Everything between Echo Summit and Highway 89 in the Christmas Valley — in South Lake Tahoe — is now under an evacuation warning.

More and more firefighters have been called in to attack the blaze, considered the No. 1 priority in the nation due to the number of residents, property and infrastructure it’s threatening. On Friday, there were 3,200 personnel working on containing the blaze, an increase from roughly 2,900 on Thursday, and more than 18,000 structures were under threat.

Crews are actively working to identify locations where the fire could jump containment lines and put in contingency — or backup — resources, Horner said. Spot fires have ignited consistently since the blaze began, with winds pushing embers into dry, receptive terrain. Firefighters are also constructing larger containment lines and dropping retardant and water from above when conditions allow, officials said.

Flames on Friday were forecast to pass through Pollock Pines, a community along the northwest portion of the fire, and firefighters for the past few days were “prepping the area for the fire coming toward all those homes,” including bringing in more equipment and personnel, Horner said.

Winds that have plagued the burn area were supposed to abate, but on Thursday, afternoon gusts up to 30 mph struck the northeast edge of the fire, Horner said. Flames that were just “skunking around” shot up to elevations of about 6,800 feet north of Highway 50, where several small communities dot the landscape, he said. It set tree tops aflame — known as crowning — drastically increasing temperatures and the rate of fire spread.

When the gusts struck, the sun was out, an inversion layer over the fire had lifted and the air was bone-dry — all conditions that made it “primed for ignition,” Horner said, adding that he watched the activity in real time: “It was moving fast, really increased temperatures.”

At that point, the only way to slow the blaze is to drop retardant and water on it from the air, Horner said. Crews dropped roughly 20,000 gallons of retardant in the northeastern area alone on Thursday, he said.

Temperatures are heating up, though Horner said it can be hard to gauge when you’re under large plumes of smoke sent up by the flames. “When you’re in the smoke ... you can’t even see the sky or the sun, the sun is turning orange,” he said.

Times staff writer Hayley Smith contributed to this report.

This story originally appeared in Los Angeles Times.

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