LIGHT WINDS AND scattered thundershowers today helped to calm the flames of a huge wildfire that has prompted evacuations north of Los Angeles.

Firefighters were hoping to rein in the blaze before temperatures spike later in the day.

An enormous plume of smoke was visible across much of southern California after the fire broke out yesterday afternoon in dense forest land.

The blaze exploded in size within hours, including some areas that have not burned since 1968, fire officials said.

By nightfall, the flames had consumed more than 15.5 square miles of timber and shrubs. There was no containment.

About 100 rural homes were evacuated in the Lake Hughes area of the Angeles National Forest, about 60 miles north of LA.

Preliminary damage assessments found at least three structures burned.

It was not immediately clear if they were houses.

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

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

The area is expected to have temperatures of about 35C or higher through the weekend.

Evacuation centres were designated for residents and animals but because of Covid-19 concerns, people were told to stay in their cars.