Firefighters struggled Friday to get ahead of a raging wildfire that has moved dangerously close to heavily populated areas around this idyllic coastal city and forced the evacuation of roughly 30,000 people.

Mobile home parks and neighborhoods of multimillion-dollar mansions were like ghost towns, bathed in the eerie orange glow of the growing blaze as billows of smoke wafted over the blackened mountains.

Santa Barbara County spokeswoman Jodi Dyck said the fire had grown since Thursday night, when it measured roughly 2,700 acres. By 9:30 a.m. Friday, 3,500 acres had burned.

"It really got going during the night. Some areas have 45-year fuel. The wind is all over the place," fire Capt. Mike De Pont said Friday. "For this time of year, this activity is unusual."

Conditions for fighting the fire were not expected to improve Friday, with weather forecasts calling for low humidity, wind gusts that could reach 65 mph and temperatures that could top 100 degrees, according to the National Weather Service.

After previously ordering the evacuation of an estimated 18,000 people from areas of Santa Barbara County, authorities overnight ordered another 12,000 to leave.

Two evacuation centers that could house over 1,000 people between them have been opened.

The blaze was approaching homes in the areas below the city's steep canyons. Fire spokesman Gary Pitney said flames jumped Foothill Road dividing the hilly terrain from the flatlands below and ignited spot fires in brush surrounding houses. Santa Barbara Acting Fire Chief Andy DiMizio told the Los Angeles Times that firefighters were able to stop the blaze from reaching the central section of Santa Barbara.

"The fire was threatening the city directly," he told the newspaper. "Last night, all hell broke loose."

Pitney said the fire also pushed west across state Route 154, the key thoroughfare between Santa Barbara and wine country to the north.

Kelley Gouette, a deputy incident commander with the state Department of Forestry and Fire Protection, likened the fire to "a blowtorch" and said he had requested that officials bring in a DC-10 to drop larger loads of water on the blaze.

Santa Barbara County Fire Chief Tom Franklin said the blaze was particularly tough to fight as it spread into rugged terrain with thick brush that served as fuel and limited firefighting aircraft.

Firefighters are "running pretty thin on equipment," he said.

Officials said 11 firefighters were injured, including three who were hurt when they sheltered in a house during a firestorm. On Friday, Captain Brian Bulger was released from Grossman Burn Center.

Captain Ron Topolinski was operated on Friday morning. He has second-degree burns to the head and forearms, but will not require any grafting. He will probably be released sometime this weekend, according to hospital officials.

Firefighter Robert Lopez was also operated on Friday morning. He has second- and third-degree burns to the head, shoulders and arms, totaling 15 percent of his body. He will stay in the hospital over the weekend, and likely going under a second procedure sometime next week, according to hospital officials.

Grossman Burn Center has every expectation that the two firefighters still at the hospital will heal perfectly and will both be able to resume their work duties at some point.

About 2,300 firefighters from many departments were on the lines, aided by 14 air tankers and 15 helicopters. As of Friday morning, the fire was just 10 percent contained.

The seasonal wildfires that menace this coastal city -- home to screen stars, former presidents and Oprah Winfrey -- roared to life earlier in the year than usual but their ferocity is familiar.

Firefighters have been wary of "sundowners" -- fierce winds that late in the day can sweep down from the Santa Ynez Mountains towering close behind Santa Barbara.

The benignly named Jesusita Fire was a slumbering day-old brush fire on rugged slopes above the city when a sundowner hit at midafternoon Wednesday, hurling towering flames into homes and spitting embers into more distant neighborhoods.

The city's location on the state's central coast gives it some of the best weather in the world, with temperatures routinely topping out in the 70s, and views of the Pacific Ocean. Now with a population of about 90,000, it dates to the Spanish colonial era of California and a Roman Catholic mission established in the 1780s is a major tourist attraction.

But the geography that gives it beauty and a serene atmosphere also brings danger.

In November, a wind-driven fire burned 200 houses in Santa Barbara and Montecito, including the home of actor Christopher Lloyd. Winfrey's estate escaped, along with the home of actor Rob Lowe, among many celebrities who have area homes.

Gregg Patronyk, a lifelong Santa Barbara resident whose parents' home was destroyed by fire in 1990 and who had to evacuate in November, said he began soaking his roof when he saw other houses burning Wednesday.

"It started firestorming dramatically," he said. "The fire got within 200 to 300 feet of my house. There was a lot of pressure to leave. Police wanted me out and I got a frantic call from my sister, who was walking up the hill to get me. So I packed up the car and left, picking her up on the way."

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