The raging Dixie Fire is only 21 percent contained and has scorched an area more than twice the size of New York City.
Newly clear skies in northern California will allow firefighting aircraft to rejoin the battle to contain the raging Dixie Fire, which has forced thousands from their homes and grew over the weekend to be the second-largest blaze in state history.
The thick smoke that held down winds and temperatures in the wildfire zone cleared on Monday, which authorities said would allow more than two dozen helicopters and two air tankers that have been grounded to fly again and make it safer for ground crews to manoeuvre.
“With this kind of weather, fire activity will pick up. But the good thing is we can get aircraft up,” said fire spokesman Ryan Bain.
The Dixie Fire now covers 198,007 hectares (489,287 acres) and remains only 21 percent contained, the California Department of Forestry and Fire Protection (Cal Fire) said in a Monday morning update.
It has scorched an area more than twice the size of New York City.
Last week, the blaze ravaged the historic gold rush town of Greenville, about 257km (160 miles) north of Sacramento.
At least 627 homes and other structures had been destroyed by Monday and another 14,000 buildings were still threatened in the northern Sierra Nevada.
With smoke clearing out above eastern portions of the fire, crews that had been directly attacking the front lines would be forced to retreat and build containment lines farther back, said Dan McKeague, a fire information officer with the US Forest Service.
More than 5,800 personnel have been deployed to battle the blaze, Cal Fire said on Monday.
Scientists have said climate change has made the region much warmer and drier in the past 30 years and will continue to make the weather more extreme and wildfires more frequent and destructive.
Massive fires have broken out in several countries in recent weeks, including Canada, Turkey and Greece, prompting urgent calls for governments around the world to enact long-term policies to tackle the problem.
California typically experiences peak fire season later in the year, and the state was on pace to suffer even more burned lands this year than last year, which was the worst fire season on record.
Edwin Zuniga, a spokesman for Cal Fire, told The Washington Post newspaper that the state was seeing “fire activity that even veteran firefighters haven’t seen in their career”.
Only the August Complex Fire of 2020, which consumed more than 404,685 hectares (1 million acres) in California, was larger.
So far, no deaths have been attributed to the Dixie Fire, but three firefighters have been injured.
Meanwhile, the cause of the blaze remains under investigation.
Pacific Gas & Electric has said it may have started when a tree fell on one of the utility’s power lines. A federal judge late on Friday ordered the company to explain its role, giving PG&E until August 16 to respond.