The Robbers Mill Fire in Placer County, which broke out Wednesday, grew to nearly 2,000 acres and threatened about 170 homes, Cal Fire told the San Francisco Chronicle.
The Los Angeles Times said the fire was 20 percent contained.
In Utah, rain gave a boost to fire crews battling a cluster of lightning-caused blazes in Box Elder County.
"Everybody has been praying for rain, and here it came," Teresa Rigby, a fire information officer with the Bureau of Land Management, told the Salt Lake Tribune late Saturday. "It is definitely helped us, along with the higher humidity along the fire lines — and we're expecting more rain Sunday."