Los Angeles firefighters have "turned the corner" in their battle against the "largest [wildfire] in the history" of the city, according to the city's mayor, Eric Garcetti.

More than 90 percent of the 1,400 people evacuated from their homes since the blaze began on Friday have returned.

However, officials have warned that danger still remains, with high winds posing a continued threat.

Shifting wind patterns could yet cause the fire to spread, by blowing burning embers through the rugged northern edge of Los Angeles, said Garcetti.

"This is not over ... With winds this strong anything can happen," he said.

The 2,400 hectare La Tuna Fire, named after the canyon in which it started, was considered 30 percent contained by late Sunday night, up from 10 percent on Sunday morning.

In response to the blaze, Jerry Brown, governor of California, declared a state of emergency for Los Angeles county on Sunday. The move is aimed at easing the provision of state and federal help to fight the fire.

Temperatures on Sunday were in the low 90s, down from hovering around 100 degrees Fahrenheit (38 degrees Celsius) in previous days.

Weather forecasts predict moderate weather and higher humidity in coming days, which are positive signs for containing the blaze, said Ralph Terrazas, the Los Angeles fire chief.

Wildfires in the western US have burned more than 2.9 million hectares since the beginning of the year, about 50 percent more than during the same period in 2016, according to the National Interagency Fire Center.