By nightfall more than 950 firefighters had built containment around about 20 percent of the inferno, which has blackened more than 43 square miles (111 square kilometers) of dry brush and chaparral since erupting on Thursday morning.
More firefighters were said to be on the way and fire officials said they hoped that diminishing winds and higher humidity would help them make headway overnight and on Saturday.
Fire managers said they expected it would take until next Monday to fully contain the blaze, which sent a pall of thick smoke drifting over the beach community of Malibu and farther inland across Los Angeles County.
Several farm buildings and recreational vehicles were engulfed and fire officials said 15 homes were damaged, along with five commercial properties. While 25 outbuildings were destroyed, no residential structures were lost and no injuries had been reported.
Some 4,000 homes were considered threatened, with evacuations ordered for about a quarter of those residences, the Ventura County fire and sheriff's departments said.
The so-called Springs Fire and a flurry of smaller blazes around the state this week marked a sudden start to a California fire season that some weather forecasters predict will be worsened by a summer of high temperatures and drought throughout much of the US West.
'It's only may'
"We're seeing fires burning like we usually see in late summer, at the height of the fire season, and it's only May," Ventura County Fire Department spokesman Tom Kruschke said.
The temperature in Camarillo hit a record high of 96 degrees F (36 degrees C) by late morning on Friday, according to the National Weather Service.
Strong, erratic winds that complicated efforts to combat the Springs Fire through much of the first day were calmer on Friday, officials said.
The improved wind conditions allowed several air-tanker planes equipped for dumping payloads of fire-retardant chemicals to return to the air along with a fleet of eight water-dropping helicopters.
The Springs Fire, which may have been ignited by a tossed cigarette butt, broke out at 6:30am local time (1330 GMT) on Thursday beside the US 101 freeway, less than 10 miles (16 km) from the Pacific coast.
It spread quickly to the edges of the communities of Camarillo and Newbury Park.
By Friday morning, flames had advanced to within a short distance of the ocean's edge in some places, forcing authorities to close several miles of Pacific Coast Highway.
At the Point Mugu US Naval Air Station on the coast, all non-essential personnel were ordered to stay home for a second day as flames encroached on a firing range at the extreme western end of the base, spokeswoman Kimberly Gearhart said.
She said no ammunition was stored at that location, bordered on two sides by coastline and wetlands.
But a base housing unit that is home to 110 active-duty military personnel and their families was evacuated on Friday because of heavy smoke, Gearhart said, adding there was no immediate fire threat to that vicinity and military aircraft were continuing routine flights between the base and a communications post on San Nicolas Island offshore.
In mid-afternoon, residents were ordered to clear out of more than 900 homes in Hidden Valley, an enclave of ranches and estate-type properties southeast of Camarillo.
Some 200 dwellings were evacuated earlier along the coastal highway and adjacent canyon roads, sheriff's Sergeant Eric Buschow said.
Horse trainer Bryon Wilson, 36, and his wife drove two trailers into an area of multimillion-dollar ranches around Hidden Valley Road that was later ordered evacuated.
"As we were loading the horses in (the trailers) this afternoon, the fire was right at the back of the barn, so we were in amongst it already," Wilson said.
Previous evacuation orders for two housing subdivisions at the northern end of the fire zone closer to Camarillo were lifted, but those neighborhoods remained restricted to residents carrying identification, Buschow said.
California State University at Channel Islands campus, including student housing, was closed for a second day, the university said, although official evacuation orders for the school were lifted.
A separate late-afternoon brush fire in the hills above Glendale, a suburb just north of Los Angeles and about 50 miles (80 km) east of Camarillo, prompted the evacuation of a number of homes and an elementary school.
But water-dropping helicopters and ground crews moved in to quickly contain it. A larger fire in Riverside County, east of Los Angeles, on Thursday destroyed two houses and damaged two others before firefighters halted its spread, and at least five other wildfires burned in Northern California.
Hot, dry conditions in Southern California were fed largely by Santa Ana winds blowing in from desert areas to the east.