There was barely a taste of rain on Saturday from thunderstorms that brought wind and hardly any relief, forecasters said.
The 38C heat along with strong winds offered little reprieve to the firefighters, trying to contain the Park Fire, scorching the wilderness terrain some 160km north of Sacramento, the state capital.
"We had some thunderstorms that just brought us down-drafts, that's a problem," said Christopher Young, a spokesman for California Department of Forestry and Fire Protection, or Cal Fire.
"Lightning is a factor we worry about," he said.
Firefighters from Australia and New Zealand will start arriving on Wednesday to help. (AP PHOTO)
Blazes from the Park Fire, started by an alleged arsonist who pushed a flaming car down a gully near Chico, California, on July 24, has since burned more than 162,200 hectares, an area larger than the city of Los Angeles.
The 42-year-old man arrested hasn't entered a plea as of Saturday, but was charged with arson and held without bail, officials said.
More than 560 homes and other structures were destroyed since the blaze started 11 days ago, feeding off of downed timber and tinder dry grass and brush. The fire was 27 per cent contained on Saturday, officials said.
The rough, wilderness terrain means it takes two-to-three hours to reach the fire lines, officials said.
Some firefighters are being flown to the front lines by helicopters, some expected to stay there for days with supplies also flown in.
The national wildfire season has had an intense start, raising the risk of stretching fire-fighting resources too thin.
The centre has already requested help from firefighters in Australia and New Zealand, who will start arriving on Wednesday and will be deployed to Oregon and Washington.
