A forecast that includes several days of gusting Santa Ana winds has fire officials worried about the possible spread of the 83,000-acre Woolsey Fire straddling Ventura and Los Angeles counties, officials said Sunday.

The massive blaze, which has claimed two lives and forced more than 250,000 people to evacuate from Malibu to Thousand Oaks, was 10 percent contained as of Sunday morning.

But expected wind gusts of 40 mph or stronger over the next several days have officials concerned the fire could spread in a quick and unprecedented fashion, and urged residents who were sheltering in place to evacuate immediately.

"Maybe 10 or 20 years ago you stayed in your homes when there was a fire and you were able to protect them," Ventura County Fire Chief Mark Lorenzen said. "We're entering a new normal. Things are not the way they were 10 years ago."

The fire had burned 83,275 acres as of Sunday morning, according to fire officials. A total of 177 buildings had been destroyed, and roughly 57,000 structures were threatened. The coming wind gusts could also severely reduce the effectiveness of aerial water and retardant drops, leaving firefighters to battle the flames solely from the ground, officials said.

Several parts of Los Angeles and Ventura counties, including Malibu, Calabasas, Agoura Hills, Westlake Village, Hidden Hills, and sections of West Hills, Monte Nido, Gated Oaks and Topanga, remained under evacuation order Sunday morning, officials said. Residents of Topanga Canyon who were sheltering in place were also advised to flee the area.

Evacuation orders in some parts of Ventura County, including Camarillo Springs and sections of Newbury Park, have been lifted, according to Sgt. Eric Buschow, a Ventura County Sheriff's Department spokesman. Homes were also being threatened early Sunday in the West Hills neighborhood at the western edge of the San Fernando Valley.

Two fatalities were reported Friday afternoon in the 33000 block of Mulholland Highway in Malibu, according to L.A. County sheriff’s officials. The bodies of two individuals were "severely burned inside of a stopped vehicle located on a long residential driveway," authorities said.