Almost 200,000 homes and businesses across California were without power Thursday and utilities warned that hundreds of thousands more could be in the dark soon as high winds and brittle conditions fueled fast-growing wildfires.

Those fears were being realized in Sonoma County, 75 miles north of San Francisco. The fast-growing Kincade fire flared up early Thursday and within hours covered 10,000 acres. The National Weather Service reported wind gusts of up to 70 mph, and evacuations were underway in several communities.

"Leave immediately if you are in these locations," the Sonoma County Sheriff's Office warned. "If you feel unsafe, evacuate."

Cal Fire spokesperson Jonathan Cox told KTVU-TV that the fire was growing at a "critical rate." He blamed dry conditions and the high winds.

"We are in the heart of the fire season right now," Cox said.

The bulk of the power outages, affecting at least 500,000 people, were in northern and central California, where Pacific Gas & Electric has been warning for days that high winds forecast for the state could result in preemptive power shutoffs. Residents should be ready to be without power for 48 hours or more, the company warned.

"Once the weather subsides and it is safe to do so, PG&E crews will begin patrolling power lines, repairing damaged equipment and restoring customers," PG&E said. 

That respite might not last long — the company said that strong winds forecast for Sunday and Monday could lead to more preemptive outages.

The latest wave of outages come two weeks after gusty winds, high temperatures and parched conditions forced PG&E to shut off power to 2 million people, many for several days. That preemptive outage, or Public Safety Power Shutoff, fueled outrage from many residents, but PG&E defends the outages as crucial to the safety of its customers.

Southern California: Fire in San Bernardino County

Southern California was not immune to the outages, the fire conditions or the fires Thursday. Southern California Edison had cut power to about 8,000 customers early in the day and warned that hundreds of thousands more could see preemptive outages.

A fire in San Bernardino County, about 60 miles west of Los Angeles, was only about 100 acres, but evacuations were being ordered early Thursday. Citing the outages and firem California State University, San Bernardino canceled classes Thursday.

The San Bernardino County Fire Department warned the blaze had "potential for large growth."

California experienced the deadliest and most destructive wildfires in its history in 2017 and 2018. Fueled by drought, an unprecedented buildup of dry vegetation and extreme winds, the size and intensity of these wildfires caused the loss of more than 100 lives, destroyed thousands of homes and exposed millions to unhealthy air.

Read this: California power lines spark wildfires and prompt blackouts. Why not just bury them?

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