Heatwave conditions hamper US fire crews

Crews scrambled to protect homes from a huge wildfire that prompted evacuations to the north of Los Angeles, and officials warned the blaze could flare up again as a blistering heatwave descended on California.

The fire exploded in size within hours after it broke out in dense forest on Wednesday, sending up a towering plume of smoke visible for hundreds of kilometres around.

Flames raced across ridges and steep slopes, including in some areas that had not burned since 1968, fire officials said. By Thursday night, the blaze still threatened more than 5,400 homes and had charged through 44.5 square kilometres (17 square miles) of brush and forest land.

The fire was fed by tinder-dry brush in steep terrain, but its ferocity approached that of wind-driven blazes that usually erupt when gusty Santa Ana winds arrive later in the year, said county Deputy Fire Chief David Richardson.

The blaze was only 6 percent contained. Light winds and scattered thundershowers early in the day did help firefighters tame the flames somewhat. However the short term forecast is for hot, dry weather with “near critical” fire conditions because of possible gusty winds.

“This will be a major fire for several days,” said Chief Robert Garcia with the US Forest Service.

Officials are preparing for the possibility of more extremely dangerous fires as the heat increases and humidity levels drop, fire officials said in a statement.

The area was expected to have temperatures of about 35 degrees Celsius (mid-90s Fahrenheit) or higher through the weekend.

Evacuation centres were designated for residents and animals, but because of COVID-19 concerns people have been told to stay in their cars in the parking lots.

About 100 rural homes were evacuated in the Lake Hughes area of the Angeles National Forest, some 97km (60 miles) north of downtown Los Angeles.

Preliminary damage assessments found at least three structures were burned, but authorities warned the toll is likely to be higher.

Kenny Reynolds lost his home. The fire came down the hill and across the street “engulfing on both sides”, he told KABC-TV.

Reynolds and others retreated “and then it just kind of rolled in”, he said. “It was taking everything as it kind of went down.”

The cause of the blaze, dubbed the Lake Fire, is under investigation. It is one of several wildfires burning in the region.