Firefighters battling the largest recorded wildfire in California's history have made progress in extinguishing the flames, even as the blaze grew overnight, the state fire agency said.

More than 4,000 firefighters in northern California are fighting two extensive blazes that cover more than 304,400 acres.

So far, two firefighters have been injured and 119 homes destroyed.

Although the total size of the blaze grew by about 2,000 acres overnight, firefighters were able to contain 51% of it, up from 46% the night before, the California Department of Forestry and Fire Protection (CalFire) said.

Separately, about 160 kilometres northeast, near the city of Redding, 4,700 crew members are fighting the 176,000-acre Carr Fire, which has been blamed for seven deaths, including two firefighters, and the destruction of 1,077 homes, Cal Fire said.

The Carr Fire has been 48% contained.

Firefighters have struggled against it in steep, inaccessible terrain, Cal Fire said.

Winds gusting up to 56km an hour and temperatures above 32 degrees Celsius are forecast from today to Saturday in northern California, the National Weather Service said in a Red Flag warning.

"A combination of strong winds, low relative humidity, and warm temperatures can contribute to extreme fire behavior," the service said.

Nine other major fires are burning in California, according to the National Interagency Fire Centre.

Together, the wildfires have displaced tens of thousands of people.

To the south, in the Cleveland National Forest area, the 9,600-acre Holy Fire is 5% contained, the Cleveland National Forest said on Twitter.

Officials from the Cleveland National Forest said yesterday that the blaze had destroyed 12 structures.

A 51-year-old man accused of setting the fire was arrested and charged with arson, threat to terrorise and resisting arrest, the Cleveland National Forest said on Twitter.       

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