Live updates: At least 132 structures destroyed by Mountain Fire in Ventura County

The Santa Ana winds that drove the fire expected to subside by late Friday morning.

A red-flag warning expired at 11 a.m., but firefighters still have a long way to go.

According to CAL FIRE, the blaze is burning in steep, rugged terrain, with dry and receptive fuels, which they say have challenged containment efforts.

The Santa Anas are expected to return early-to-midweek next week.

Though the winds began diminishing, the fire continued to back in areas where it hadn't been tied into control lines, CAL FIRE said.

The Santa Anas are expected to return early-to-midweek next week, according to the National Weather Service.

We're getting a better look at how the destructive Mountain Fire in Ventura County was able to spread so quickly and easily.

A 3D map of the fire area shows where the fire started near Moorpark. Hot embers were able to be carried by the wind for three miles, allowing the flames to the jump the 118 Freeway. That's when the the fire made its way into more densely populated neighborhoods in Camarillo.

While you can't stop the spread of embers, there are other steps you can take to help protect your home. During red flag warning days, experts say small improvements to weak points around your home, such as vents and garage doors, could make a significant difference.

"When you leave for the day, close the windows in the house. Do things so that your house isn't so open and available and porous to wind or embers, or other issues that might present themselves during the day," said Yana Valachovic with the University of California Agriculture and Natural Resources.

We're getting a better look at how the destructive Mountain Fire in Ventura County was able to spread so quickly and easily.

Some Camarillo residents are offering their support to those who lost their homes in the Mountain Fire.

Peter Nichols told Eyewitness News though he's grateful he still has his home, he has great empathy for his friends whose homes were destroyed.

"Nobody knew anything about our house, whether it was still here or not," he said. "From the top of the street, we could see the roof of this house. It's just overwhelming. I cried like a baby. My wife and I hugged."

Many said the Mountain Fire reminds them of the the 2018 Woolsey Fire, which killed three people and destroyed 1,600 homes.

Many said the Mountain Fire reminds them of the the 2018 Woolsey Fire, which killed three people and destroyed 1,600 homes.

Investigators are working hard to determine what sparked the wind-driven Mountain Fire, which quickly scorched more than 20,000 acres in Ventura County.

Firefighters believe the blaze started Wednesday morning in Somis, but they don't yet know the cause.

Brian Williams, who has lived in Somis for 22 years, recalls seeing the smoke pour into the sky that morning after his wife called him.

"Around 9 a.m. she called me and there was smoke coming up over the back of our property pretty fast. I head home and halfway home she said she could see flames, we have a back pasture. It had already encroached onto the house. It was chaos. They had evacuated. The fire was approaching the house."

Investigators are still trying to determine what sparked the Mountain Fire, which spread to more than 20,000 acres and destroyed dozens of homes in Ventura County.

Ventura County Fire Capt. Trevor Johnson says they haven't determined the origin.

"No idea on the cause of the fire," Johnson said. "Again, we are fully committed to bringing resolve to the incident. That is a part of our incident management strategy. But that's under investigation currently."