New evacuations have been ordered in California as officials warn wildfires could spread because of extremely strong winds.
Some 50,000 residents in the towns of Windsor and Healdsburg, north of San Francisco, have been told to move.
Meanwhile, Pacific Gas & Electric (PG&E) said it would turn off power in 36 counties for 48 hours or longer, affecting up to two million people.
There are fears wind gusts could hit power lines, causing new fires.
A state of emergency has been declared in Los Angeles and Sonoma counties, and thousands of firefighters were still battling flames.
The Kincade Fire, which started on Wednesday, has burned through 25,455 acres (10,300 hectares) of land in Sonoma County, one of California’s best-known wine regions.
The fire was burning in remote steep terrain making access difficult, the state fire department said. On Saturday, it was about 10% contained.
Winds in the region were expected to pick up from 20:00 local time on Saturday (03:00 GMT on Sunday) and gusts were forecast to hit 85mph (137km/h).
The National Weather Service issued a “red flag” warning for areas around the Kincade Fire, which had destroyed some 50 structures.
On Saturday, PG&E warned about 940,000 homes and businesses could be impacted by the power cut between Saturday evening and midday on Monday.
The warning from PG&E came as the company faced scrutiny over its possible role in the fires.
In suburban Los Angeles, the Tick Fire had charred 4,615 acres and was 25% contained, according to county officials. All residents who were told to evacuate have returned home.
Nine structures were destroyed but no injuries were reported.
BBC correspondent Peter Bowes lives in the Santa Clarita area north of Los Angeles, where the Tick Fire has been raging.
“My partner was in the house and had just seconds to get out, to pick up the dog, throw the dog in the car – gently – just get out. It happened that quickly and all our neighbours did exactly the same thing,” he said.
He later tweeted photos of the devastation.
According to a report filed to the California Public Utilities Commission on Thursday, a “broken jumper” – which connects power lines to towers – was discovered at 21:20 on Wednesday.
The fire began at 21:27, according to the California Department of Forestry and Fire Protection.
The news sent share prices of PG&E tumbling on Friday, as investors feared the company might be held responsible for the Kincade Fire.
The company is already seeking bankruptcy protection as it faces lawsuits over last year’s Camp Fire, which killed 85 people.
The deadliest wildfire in the state’s history was sparked by ageing equipment owned by PG&E. It spawned billions of dollars in liability claims against the company.