The Mendocino Complex Fire has now grown larger than the city of Los Angeles, measuring at least 302,086 acres.
The huge size of the Mendocino fire has led to the announcement that fire crews will be unable to fully contain the blaze until early September.
Holy Fire is also growing at a rapid pace, now measuring 9,600 acres – more than doubling in size in less than 24 hours.
It remains only five percent contained according to the National Forest.
A man has been arrested in connection with the Holy Fire, and remains in Orange County Jail on a $1million bond.
Residential areas are now at risk, with 200,000 people in southern California facing mandatory evacuations due to the Holy Fire.
“Firefighters continue to battle the blaze around the clock,” the National Forest said in a tweet.
“We expect favorable weather conditions this weekend to help these efforts.”
Where are the largest fires in California?
Mendocino Complex Fire
The Mendocino Complex Fire is located at Ukiah and Hopland, in north-west California and is made up of two fires.
Officials have estimated it has grown to 302,086 acres, with 47 percent containment
The Carr Fire is in Whiskeytown, northern California and sparked from a vehicle failure.
At present, it consists of 176,069 acres and is 47 percent contained.
The Donnell Fire in Stanislaus National Forest, eastern California and first ignited on August 1.
It has grown to 17,941 acres in just over a week, four percent of which has been contained.
The Natchez Fire is just south of the Oregon-California border in Happy Camp, California.
Beginning from a lightning strike – the fire has grown to reach 11,338 acres with 50 percent containment.
The Holy Fire is in southern California, in the Orange and Riverside counties which are the most populated in the state.
Latest updates place the fire at 9,600 acres with five percent containment.
Follow express.co.uk live blog here for latest updates on the California wildfires.