UPDATE 6:27 p.m.: (AP) Officials say all 8,000 people evacuated from homes in Mendocino County have now been allowed to return.
Tens of thousands of evacuees in other hard-hit counties, including Napa and Sonoma, are still waiting for permission to go back to their communities.
County and state officials reported progress in fighting fires but warned that recovery from the devastation will take years.
UPDATE 3:31 p.m.: Many evacuation orders in Northern California have been lifted after the deadliest week of wildfires in the state’s history. But officials with CAL FIRE cautioned that fire season is far from over, and said crews still have to be ready to take on new fires anywhere in the state.
Help has come in from hundreds of firefighters and engines from 17 states, including as far away as New York, Florida and even Australia, said CAL FIRE Assistant Deputy Director Daniel Berlant.
“We’re very fortunate that currently there’s not a lot of other fire activity in the nation, so a lot of those fire resources from the U.S. Forest Service, both fire engines, equipment, as well as air tankers, are here in California assisting us in our battles,” Berlant said.
Thank you to all our fire partners from across the U.S & Australia that came to California's aide during our greatest time of need. pic.twitter.com/0dljNiiB7i— CAL FIRE (@CAL_FIRE) October 16, 2017
Berlant said the biggest and most destructive wildfires tend to happen in October, and keeping crews ready across the state has been essential, with gusty winds threatening to kick up new fires in Southern California.
The Canyon 2 Fire in the Anaheim hills and burns near San Diego have caused significant damage already. CAL FIRE's Michael Mohler said fires behave differently based on where you are in the state.
"When we talk about a red flag warning in Southern California, its usually followed up with what we call traditional Santa Ana wind," Mohler said. "The winds that we experience across the Northern state, can create a red flag warning. But those winds can come out of several different directions which increase the explosive fire growth."
Mohler says the brush or fire fuel is more intense in the north compared to the douth, but its still yearlong fire season statewide.
Many wildfire evacuees got the green light over the weekend to head back into their neighborhoods. All Solano County residents and most of those in Napa County impacted by the Atlas Fire were able to return home.
All evacuation orders have been lifted for people in areas of the Cascade, LaPorte, Lobo and McCourtney fires. The Yuba/Sutter Fairground remains open as a shelter. Calistoga and some other areas affected by the Tubbs Fire have been opened as well.
At least 40 people have died during the deadliest week of wildfires in state history. The victims include a couple who recently celebrated their 50th wedding anniversary and a woman born with a spinal defect who worked to help others despite her own troubles.
The danger is far from over, but smoky skies have started to clear in some places. Emergency officials are reminding residents to stay prepared, as many of these areas are still under advisories. Anyone who sees downed electrical wires should call Pacific Gas and Electric Company immediately.
PG&E says it expects to restore power to all its customers in the fire zones later today.
The utility company says it's restored power to more than 92 percent of homes and businesses that lost electricity during the wildfires, but about 21,000 customers remain without power.
After the wildfires broke, PG&E turned off gas service to about 42,000 customers in the affected areas of Napa, Sonoma and Mendocino counties.
Nearly 900 workers, from PG&E and from other energy companies, have been working to relight pilot lights in areas where it's safe to do so. The company says safety work on gas pipelines should be completed Monday morning. It wasn't immediately known when service would be fully restored.
Capital Public Radio's Sally Schilling, Steve Milne, Daniel Potter and Chris Remington contributed reporting for this story.