A short respite from triple-digit heat allowed crews battling several wildfires in Southern California to block the flames from destroying homes this week, but dangerous red flag fire conditions have returned, the National Weather Service said Thursday.
Temperatures in the Los Angeles, Ventura and Santa Barbara county mountains and valleys were expected to hover in the 90s Thursday, but they could climb into the 100s by the weekend while coinciding with a drop in humidity and strong wind gusts, NWS meteorologist Todd Hall said.
A red flag warning — meaning weather conditions are prime for a fast-moving, destructive wildfire — was in effect for the those three counties, while a heat advisory was expected in Orange, San Diego and Riverside counties, the weather service said. It will get worse through the weekend, Hall said.
Several wildfires have broken out across Southern California since a heat wave settled over the region late last week.
The San Gabriel Complex fire, a pair of wildfires burning in the San Gabriel Mountains above Duarte, began Monday and forced hundreds of evacuations.
"When we drove away, I thought we had a 50-50 chance of seeing our house again," said Roger Bosch, a Duarte resident.
On Wednesday, relief washed over the 73-year-old: He got to go home. Evacuations were lifted as conditions improved and firefighters increased containment of the two fires.
Of the 858 homes evacuated in the foothills areas, 534 households were allowed to return, Los Angeles County Sheriff's Capt. David Halm said. Mandatory evacuations remained in place for other parts of Duarte and Azusa, authorities said.
The fires have burned 5,235 acres and were 15% contained, officials said Thursday.
The battle against the flames was aided by cooler temperatures and higher humidity in the days following Monday's record-breaking heat, authorities said. Steep, challenging terrain presented a problem, said Mike Wakowski, the commander for the multiagency wildfire effort.
"We're trying to secure as much as possible before the next heat wave comes," Los Angeles County Fire Department Deputy Chief Vince Peña said Wednesday.
Conditions improved enough this week in Santa Barbara County that crews began leaving the Sherpa fire burning in the Santa Ynez Mountains and Los Padres National Forest. That fire has burned 7,486 acres and was 93% contained, the U.S. Forest Service said.
Three hot shot crews dropped onto the mountain earlier this week to help build defenses at the fire's most isolated points deep in the forest, the Forest Service said.
In San Diego County, firefighters have increased containment of the Border fire just north of the U.S.-Mexico border that prompted mandatory evacuations for the entire east county community of Potrero. The Border fire was about 20% contained and has burned 6,840 acres, according to the California Department of Forestry and Fire Protection.
The Border fire has destroyed four outbuildings and left three firefighters with minor injuries. The cause is under investigation.
Times staff writer Hailey Branson-Potts contributed to this report.
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