Wildfire fueled by monster winds races through Sonoma County, leveling buildings

The Kincade Fire ignited Wednesday night in Sonoma County, and burned 10,000 acres by the next morning. It was fueled in part by high winds that had already prompted California electric utilities to intentionally cut power to thousands of residents.

The blaze had claimed an unknown number of structures by early Thursday afternoon, Cal Fire Incident Commander Mike Parkes said at a news conference. It was unclear how many of those lost were homes.

"We expect the fire to grow," Parkes said, adding that authorities anticipate updating the acreage burned later in the day after they have a better opportunity to map the fire. They are confident, he added, that the fire is probably "at or above 10,000 acres."

"The rugged terrain, the rapidly expanding incident and the darkness last night made it tough to get a good, accurate picture of the amount of acreage," he said.

Approximately 500 personnel were fighting the fire, officials said, but it was still 0% contained.

The winds had started to die down by Thursday afternoon, officials said at a news conference, but an estimated 2,000 residents were still under evacuation orders.

Among the communities under mandatory evacuation order was the entirety of Geyserville, about 80 miles north of San Francisco. The Sonoma County Sheriff's Office told residents Thursday morning to leave since the fire crossed Highway 128, heading west.

"If you're in Geyserville," the sheriff's office said, "leave now."

Fire comes during intentional power outages

The fire erupted the same day that California's largest utility started another round of intentional power cuts to prevent its equipment from sparking wildfires. It is burning near the outage footprint in Sonoma County, Pacific Gas & Electric officials said.

The latest blackouts will continue at least through Thursday in parts of 17 counties, including Sonoma's wine country. Red flag warnings are in place for more than 25 million people in Northern and Southern California, which means soaring temperatures, low humidity and strong winds will increase fire dangers.

Winds are expected to die down in Northern California by the afternoon, CNN meteorologist Chad Myers said, but could pick back up on Sunday.

Another big wind event is forecast later Thursday for Southern California, Myers said, where gusts could reach up to 65 mph.

"One spark will take a fire a long way," Myers warned.

Southern California Edison (SCE), another utility in that part of the state, shut off power to more than 15,000 customers elsewhere in the state, in Kern, Los Angeles, Riverside, San Bernardino and Ventura counties.

Farther south, more than 320 customers in Descanso and Alpine lost power after San Diego Gas & Electric turned it off, citing "high winds and dangerous weather conditions."

Blaze burned 5,000 acres in three hours

The Kincade Fire started at 9 p.m. Wednesday (midnight ET) and torched more than 5,000 acres within three hours, Sonoma County Sheriff's Sgt. Juan Valencia said. At that rate, a football field would be burned every three seconds, according to CNN meteorologist Brandon Miller.

Parkes said the blaze started in the area of the Geysers geothermal plant in Geyserville. The company that operates the plant, Calpine, "de-energized" its local power line system before the fire started, Calpine vice president of external affairs Brett Kerr said in a statement to CNN.

The fire was spurred overnight by what authorities believed were 60 mph winds, Parkes told reporters.

As the fire burned, winds gusted up to 76 mph nearby, the National Weather Service said.

The River Rock Casino has been asked to evacuate, along with additional areas east of Geyserville, the sheriff's office said. The American Red Cross has set up two evacuation centers.

Residents in an unincorporated area near Healdsburg were under an evacuation warning, Sonoma County Sheriff Mark Essick said. "That means we want you to prepare to leave ... at a moment's notice," he said.

The sheriff urged residents to heed those evacuation orders, not only for their safety, but for firefighting efforts.

"It helps us to fight the fire," he said, "rather than have to rescue someone from their home."

Ash was "falling like snow," early Thursday in the burn zone, fire data scientist Nicholas McCarthy tweeted, referring to the burned residue as "pyrometeors."

In October 2017, the Tubbs Fire ravaged tens of thousands of acres in Sonoma County and killed nearly two dozen people. In Santa Rosa alone, a fire wiped out thousands of homes in the city roughly 50 miles northwest of San Francisco.

"This is an emotional time for many people," Essick said. "It's only been two years since the fires that devastated our community, and for many this will be a very stressful and anxious time."

Old Water Fire threatens Southern California

Another fire in San Bernardino County in Southern California prompted mandatory evacuation orders for at least 80 homes, according to the San Bernardino National Forest Service.

The Old Water Fire broke out around 2 a.m. Thursday and spread to about 75 acres within a few hours, the forest service said. An evacuation center has opened at San Gorgonio High School.

Firefighters were making progress, the forest service said, and containment was at 30%.

Approximately 400 personnel were fighting the Old Water Fire, aided by 50 fire engines and a helicopter.