Firefighters slow growth of Oak Fire burning near Yosemite

Firefighters significantly slowed the spread of a huge wildfire burning in forest near Yosemite National Park, where thousands of residents of mountain communities were still under evacuation orders Monday and smoke was spreading for hundreds of miles around.

Crews "made good headway" against the Oak Fire, according to a Sunday night incident report by Cal Fire. "Fire activity was not as extreme as it has been in previous days."

More than 2,500 firefighters with aircraft support battled the blaze that erupted Friday southwest of the park near the town of Midpines in Mariposa County. Officials described "explosive fire behavior" Saturday as flames made runs through bone-dry vegetation caused by the worst drought in decades.

By Monday morning, the blaze had consumed more than 26 square miles of forest land, with 10% containment, Cal Fire said. The cause was under investigation.

Firefighters working in steep terrain on the ground protected homes Sunday as air tankers dropped retardant on 50-foot flames racing along ridgetops east of the tiny community of Jerseydale. Personnel face tough conditions that include steep terrain, sweltering temperatures and low humidity, Cal Fire said.

Light winds blew embers ahead into tree branches "and because it’s so dry, it’s easy for the spot fires to get established and that’s what fuels the growth," said Cal Fire spokesperson Natasha Fouts.

Smoke drifted about 200 miles north toward Lake Tahoe and the same distance west into the San Francisco Bay Area, pollution control officials said.

"Hazy skies may be visible and the smell of smoke is possible at high elevations," the Bay Area Air District said on Twitter.

Evacuations were in place for over 6,000 people living across a several-mile span of the sparsely populated area in the Sierra Nevada foothills, though a handful of residents defied the orders and stayed behind, said Adrienne Freeman with the U.S. Forest Service.

"We urge people to evacuate when told," she said.