SANTA BARBARA, Calif. -- A wildfire raced across the dry hills above the California city of Santa Barbara on Tuesday morning, forcing thousands of evacuation orders and drawing hundreds of firefighters who are trying to stop the flames from reaching homes.
The Cave Fire started in the Santa Ynez Mountains a few miles northwest of Santa Barbara late Monday afternoon and had scorched more than 4,200 acres by late Tuesday morning, fire officials said.
The wind-stoked fire has threatened structures including multimillion-dollar homes and ranchettes. But so far, no homes have been burned, and only one nonresidential building has been destroyed, Santa Barbara fire Capt. Daniel Bertucelli said.
The fire had no containment Tuesday morning, but "we're slowly making progress on it," county fire Battalion Chief Anthony Stornetta said.
Firefighters at night were working "under some of the toughest firefighting conditions anywhere in the world," Los Padres National Forest Fire Chief Jimmy Harris said, in part because high winds were pushing flames downhill and then back uphill.
"It was really messy last night ... the wind pushed it in every direction, and we're trying to get it and keep a perimeter," Stornetta said.
More than 5,400 people were under evacuation orders in areas north of Santa Barbara on either side of State Route 154, but about 4,000 were expected to be able to return by around noon Tuesday, Sheriff Bill Brown said.
The fire jumped over portions of 154, and the flames and smoke made for terrifying moments for motorists trying to escape the area on the fire's first night.
One Twitter user posted frightening footage of a drive through the inferno, with flames coming right to the edge of the road.
"Please stay safe for anyone living close to the 154 and to the firefighters up there right now," the user said. "Just made it down safely and my eyes still can't believe what's happening."
The fire's cause wasn't immediately known.
Fire threatening power transmission lines
Santa Barbara County declared an emergency late Monday, saying in a news release that the fire was beyond the capabilities of the county's firefighters to control alone.
Help has arrived from outside the county. A Los Angeles County Fire Department helicopter, for instance, dropped water onto areas near homes, "stopping those flames as they advanced on those homes," county fire department spokesman Mike Eliason told CNN affiliate KSBY.
Fixed-wing aircraft have been dropping retardant onto the area during daylight Tuesday.
Dry vegetation, low humidity and wind gusts of up to 45 mph helped the fire spread Monday night into Tuesday, Harris said. Winds were more calm Tuesday -- gusts were expected to reach up to around 15 mph, the National Weather Service said.
Rain is expected, raising concerns about runoff
Rain is likely in the Santa Barbara area from late Tuesday into Thursday, the weather service says.
While that could help extinguish some hotspots, it also could lead to dangerous runoff -- debris and mud flowing across freshly burned areas onto roads, Eliason told KSBY.
Because runoff could flow onto the 154 highway, Eliason suggested that commuters consider approaching Santa Barbara via US 101 instead.
"It doesn't take a lot to impact 154 on a normal rainy day, but with all this (potential) runoff, it's going to create a big problem for drivers," he told KSBY.
The fire also was threatening Southern California Edison's main transmission lines that provide electricity to the southern portion of Santa Barbara County, officials said.
Some lesser lines have been intentionally powered down because of the fire, Eliason told KSBY. About 215 customers were without electricity service Tuesday morning, according to the outage-tracking website poweroutage.us.
While California utilities in recent months have proactively cut power to lessen the chances of wildfires during harsh weather conditions, Santa Barbara's outages were not planned before the fire happened, county officials said.
Santa Barbara City College canceled classes Tuesday and Wednesday because of the fire, as a precaution. Primary and secondary schools in the area already were closed this week for Thanksgiving break.