Updated

A cool sea breeze provided some relief for firefighters battling a blaze that has destroyed scores of homes in California, but they feared dry inland winds could return to stoke the fire on Saturday.

"Sundowners," fierce local winds that sweep down the mountain slopes from north to south and out to sea, are being blamed for fanning a small wildfire into a savage inferno that has consumed 8,600 acres and about 80 homes, menacing this celebrity enclave and other coastal towns.

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Firefighters were hoping for more sea breezes that could help temper the blaze, which was only 10 percent contained Friday night.

"When the air is coming off of the ocean the humidity is fairly high and it pushes the fire back away from the community," Santa Barbara County Fire Chief Tom Franklin said. "But the (sundowner) prediction is still there. The winds could surface, change back around and blow the fire back downhill."

Franklin said that on Saturday "there's supposed to be a significant change in that weather pattern, so we're all keeping our fingers crossed."

The National Weather Service said the sharp north-to-south pressure gradient creating the winds was expected to weaken but remain strong enough to produce gusts through Saturday, and possibly until Sunday morning.

Meanwhile, the wildfire continues raging along a five-mile front above normally serene coastal communities, forcing more than 30,000 evacuations. Authorities urged another 23,000 people to remain ready to leave at a moment's notice despite the possibility of improving weather conditions and the arrival of a huge firefighting jet.

"There will be a point in the incident when I will have cautious optimism but I'm not there yet," said Joe Waterman, the overall fire commander from the California Department of Forestry and Fire Protection.

On Friday columns of smoke boiled off the Santa Ynez Mountains after a fierce overnight battle with the blaze, repeating a pattern of relative calm in daylight and explosive behavior when winds arrive in the evenings.

"Literally last night, all hell broke loose," Santa Barbara city Fire Chief Andrew DiMizio said Friday morning, recounting firefighters' efforts to put out roof fires and keep flames out of the city proper.

About 80 homes have been destroyed in neighborhoods on ridges and in canyons that rise up the foothills above the north edge of Santa Barbara.

The city and adjacent communities, pinched between the coast on the south and the rugged mountains on the north, are subject to the sundowners.

The Santa Barbara area has long been a favorite of celebrities. Oprah Winfrey has an estate in Montecito, where Charlie Chaplin's old seaside escape, the Montecito Inn, has stood since 1928. A ranch in the mountains that Ronald and Nancy Reagan bought became his Western retreat during his presidency.

The fire's activity forced expansion of mandatory evacuation areas and evacuation warning areas as the blaze pushed west toward neighboring Goleta and east into a small portion of tony Montecito.

Some 3,500 firefighters were on the scene along with 428 engines, 14 air tankers and 15 helicopters. A DC-10 jumbo jet tanker capable of dumping huge loads of retardant began making runs on the fire Friday afternoon.

Officials said 11 firefighters had been injured to date, including three who were burned in a firestorm Wednesday. They were reported in good condition at a Los Angeles burn center.

The cause of the blaze, which broke out Tuesday, remained under investigation.