All evacuation orders were lifted at Camp Pendleton, where firefighters gained ground on a wildfire that has burned about 2,500 acres, or 4 square miles, of dry brush.
About 230 residents were allowed to return to their housing unit near Lake O'Neil Sunday evening, base officials said in a statement. Some 30 patients evacuated from Naval Hospital Camp Pendleton because of a power outage have been returned and the facility is fully functional.
The blaze at the Marine Corps coastal base was 41 percent contained as of Monday morning. The fire danger began to subside with calmer winds late Sunday. A statement from the base said officials expect to contain the fire by Tuesday.
The fire broke out Saturday amid hot, dry and blustery conditions throughout the region.
Hospital corpsman Ryan Anderson is stationed at the Marine Corps base. He told KPCC that he and his wife, Kelly, initially thought a helicopter had crashed when they first saw thick, black plumes of smoke.
"The fire was basically consuming the hillside, but it was doing it at a slow pace. Then all of the sudden — as you can see in her video — the wind picked up and it just turned it into a huge blaze. I mean the flames started going 40 feet high. You could see, like, fire tornadoes spinning up out of it at the top of the mountain. It was just crazy," Anderson said.
Nearly 340 firefighters were at the scene. The fire's cause was under investigation.
About 40 miles to the north, a fire sparked in a mulch pile at a nursery near Santiago Canyon in Orange County prompted the voluntary evacuation of 23 residents on Sunday.
The fire was not threatening homes and an RV park in the area, but residents were asked to leave because of heavy smoke and in case a spot fire is ignited, said Orange County Fire Authority Capt. Steve Concialdi.
The blaze burned an outbuilding and quickly charred about 50 acres of surrounding wild vegetation. One firefighter suffered a minor injury.
"Mulch piles get hot, and when a fire breaks out it's hard to douse the flames," Concialdi said.
The powerful Santa Ana winds that kicked up late Thursday subsided by Sunday evening. The fierce winds triggered a red flag warning of extreme fire danger from the National Weather Service, which called the situation the region's "most significant fire weather threat in the past five years."
A peak wind gust of 90 mph was recorded Saturday morning at Laguna Peak in Ventura County.
Wind gusts of 65 mph were reported near the area of a small fire that began Saturday near a key freeway interchange in northern Los Angeles County. The effort to put out the fire brought traffic to a standstill for about 90 minutes.
The driver of a big rig that went off U.S. 101 in Oxnard and crashed into a car dealership said wind was a factor in the crash, police in the Ventura County city said. The crash set off a fire that spread to vehicles in the lot.
Forecasters said the summer-like weather is expected to shift by midweek, when a storm system could bring much cooler temperatures, rain and possible mountain snow to southwest California.
This story has been updated.