The Hughes Fire, about 50 miles (80 km) north of Los Angeles, broke out on Wednesday as emergency services continued to battle two fires on the city's eastern and western flanks that have burned for more than two weeks.
The Hughes Fire quickly burned some 10,176 acres (41 square km), but that figure held steady throughout the day as 4,000 firefighters dropped water and retardant from the air and used hand tools and hoses on the ground.
Containment, a measure of the perimeter that is under control, grew to 24 per cent, up from 14 per cent earlier in the day, the California Department of Forestry and Fire Protection (Cal Fire) said on its website.
Firefighters battle new and existing blazes around the Los Angeles region. (AP PHOTO)
The Hughes Fire had led to evacuation orders for 31,000 residents and evacuation warnings for a further 16,000 people as it sent plumes of smoke over hilly terrain in the Castaic Lake area near Santa Clarita.
Firefighters contended with strong winds and low humidity that were expected to persist throughout Friday. Rain and mountain snow has been forecast for the Los Angeles area from Saturday to Monday, which could bring some relief but also create other risks.
"Impacts will likely be minimal, except for the small but non-zero threat of a thunderstorm moving over a burn area," the National Weather Service warned.
The rain could cause mudslides, Los Angeles Mayor Karen Bass warned during a news conference on Wednesday, saying the city was taking "aggressive action" by installing barriers, removing fire debris and diverting stormwater.
In the metropolitan area, Eaton and Palisades fires burned for the 17th consecutive day after incinerating entire neighborhoods, killing 28 people and damaging or destroying nearly 16,000 structures.
The Eaton Fire was 95% contained and the Palisades Fire 72% contained, Cal Fire said.
A series of smaller fires have also menaced the area including the Sepulveda Fire, which began early Thursday morning and burned along the 405 freeway near the Getty Center museum - home to numerous art treasures. The brush fire, which has blazed through 45 acres and was 60% contained, briefly caused part of the heavily traveled highway to be closed and forced some evacuations.
President Donald Trump is scheduled to visit California in the wake of catastrophic wildfires. (AP PHOTO)
California's bipartisan package of state relief was announced by Newsom as President Donald Trump was scheduled to the state on Friday to survey the fire damage.
The state aid will pay for ongoing operations, disaster recovery, debris removal and other works. Billions more dollars of federal aid will be needed for a disaster that private forecaster AccuWeather has estimated could cost more than $250 billion damage and economic losses.
Trump, speaking in a Fox News interview on Wednesday, threatened to shut off federal funding unless California altered its water management.
"I don't think we should give California anything until they let water flow," Trump said during the interview at the White House.
Trump's criticisms of California water management are completely unrelated to the issues surrounding the potential cause of and response to the fires, Newsom said.
For example, Trump said California conservation efforts in the northern part of the state were responsible for fire hydrants running dry around Los Angeles - a misstatement or misunderstanding of what happened when three local reservoirs in the Palisades area ran out of water as firefighters tackled the fire.
"The State Water Project has nothing to do with water supply as relates to fire suppression for municipal systems," Newsom told a press conference. "It's very damaging when people believe such misinformation."
