Firefighters in southern California have gained ground on a wildfire that has ravaged more than 100 structures as gusty winds subsided.

Evacuation orders have been downgraded to warnings for residents in several areas of Ventura County, where the Mountain Fire held at around 32 square miles and was 21% contained, authorities said.

Firefighters were aided by lighter winds, mild temperatures and low humidity, which let fuels dry out and burn off quickly, according to meteorologists from the National Weather Service.

Building engulfed in flames
A home burns in the Mountain Fire in Camarillo, California (Marcio Jose Sanchez/AP)

“We had a very successful day with the favourable weather,” Ventura fire chief Nick Cleary said of Saturday.

The fire broke out last Wednesday morning and exploded in size amid the arrival of dry, warm and gusty winds, forcing thousands of residents to flee and threatening 3,500 structures in suburban neighbourhoods, ranches and agricultural areas around the community of Camarillo.

More 100 structures were destroyed and another 25 damaged, fire officials said after inspection teams fanned out to evaluate the impact.

Agriculture officials assessing the toll on farmland sown with avocado, citrus fruits and berries have estimated the damage at 2.4 million US dollars (£1.8 million), local reports said.

Man surveys fire damage
Louie Gonzalez visits what remains of his mother’s home after it was destroyed in the Mountain Fire in Camarillo (Jae C Hong/AP)

Smoky air hangs over the area and it is expected to linger for several days. But forecasters said weather conditions will remain favourable on Sunday and Monday with low temperatures and an onshore breeze.

Another round of north-east winds is expected on Tuesday, but humidity is expected to rise and gusts are not expected to surge as high as those that fanned the fire, National Weather Service meteorologist Ryan Walbrun said.

The region north-west of Los Angeles has seen some of California’s most destructive fires over the years. The Mountain Fire swiftly grew from less than half a square mile to more than 16 square miles in little more than five hours on Wednesday, with gusts topping 61mph.