More than 400 structures are threatened and hundreds of people and animals have been evacuated as a fire burning for three days in Butte County continues to grow.
Officials with the California Department of Forestry and Fire Protection are warning that erratic winds mean the direction of the nearly three-square-mile Swedes Fire can change directions rapidly.
The fire is 20 percent contained.
The 700 firefighters on the scene are among 5,000 firefighters battling 10 wildfires burning in California.
The National Weather Service has issued a red flag warning for coastal counties from Mendocino to Monterey due to the possibility that dry lightning and gusty winds could create dangerous fire conditions.
A fire weather watch begins Monday for the Northern California mountains and foothills. Predicted thunderstorms could heighten fire danger.