Remains of seven more victims have been found after a number of blazes devastated the state, bringing the total death toll to 63.
The revised official roster of 630 individuals whose whereabouts and fate remained unknown is more than double the 297 listed earlier in the day by the Butte County Sheriff's Office.
More than 9,000 firefighters from across the country, using more than 1,000 engines, have been battling the blazes, including the Camp Fire and the Woolsey Fire, around 500 miles (805km) to the south.
The damage tally continues to increase for the most destructive wildfire in the state's history.
Information for contacting the Federal Emergency Management Agency for assistance was posted on a board that allowed people to write the names of those they believed were missing.
Betsy Totten, a Chico city spokeswoman, said it's unclear what will be done if people don't leave, but officials don't plan to kick them out.
The fire is now 40 percent contained, according to the California Department of Forestry and Fire Protection and the Butte County Fire Department. Evacuees milling in the parking lot faced morning temperatures that dropped to just above freezing and many wore breathing masks for protection from lingering smoke.
Searching has intensified in the town of Paradise in northern California which was completely obliterated in the recent wildfires. As of Thursday evening, the fire stands at 140,000 acres and is 40 percent contained.
Sheriff Honea said the list may contain people who do not know they are considered lost.
Three of the bodies were found in Paradise - a town of 27,000 that has been destroyed by the inferno.
The US President Donald Trump is due to visit fire-affected parts of the state at the weekend where he's likely to get a frosty reception. The fire was 62 per cent contained after destroying almost 550 homes and other buildings.
The fires have destroyed thousands of homes, including several exclusive residences in Malibu, where many celebrities live.