In addition to its pricey real estate, Santa Barbara County is home to a $1.5 billion agricultural industry that produces strawberries, fresh-cut flowers and leafy greens.

“It’s moving faster than what we can possibly do to contain the fire,” said Joe Rosa, a spokesman for the California Department of Forestry and Fire Protection, or Cal Fire.

In Santa Barbara, helicopters hovered in gray and smoky skies, and ashes speckled the ground everywhere, said Bonnie Marcus, who lives in an apartment in the eastern part of the city.

“I have never been in a war zone but that is what it felt like,” Ms. Marcus said.

Her phone kept buzzing with alerts about the fire, she said. Most of the residents of her apartment complex had evacuated.

By late afternoon, she was on the road to a friend’s house near San Diego with some personal pictures, work files and clothes stashed in a bag.