High winds and rugged terrain created expectations for a “very active” Apple fire in the Morongo Valley of Southern California, one fire expert said Thursday afternoon.

The Apple Fire burning in the San Bernardino National Forest was 30 percent contained and had consumed 28,085 acres Thursday.

“Out toward the Morongo Indian Reservation, we’re expecting very active fire” Thursday, fire behavior analyst  Dennis Burns said, in an early afternoon briefing. “The winds have really increased … (Wednesday) we had gusts up to 50 mph … it’s really starting to push the fire.”

But the reservation is not threatened, said Phil Southard, a spokesman for the Morongo Band of Mission Indians. He said the reservation is several miles from the Morongo Valley.

“The Morongo Band of Mission Indians is continuing to closely monitor the Apple Fire in coordination with local public safety officials. Evacuation orders affecting Morongo Reservation residents were lifted Wednesday,” Southard said in an e-mail.

The Apple Fire ignited July 31 in Riverside County’s Cherry Valley, and quickly grew to thousands of acres, fueled by gusting winds and dry brush. Later, fire officials said the blaze started from a vehicle’s faulty exhaust.

The Morongo Valley was added early Thursday afternoon, to San Bernardino County communities given evacuation warnings, meaning residents may be asked to leave if fire conditions worsen. Forest Falls, Pioneertown and Rimrock are the other areas under a warning.

Riverside County also added an evacuation warning Thursday for an area east of Whitewater Canyon, north of the 10 Freeway and west of Highway 62 and south of the county line — also in the Morongo Valley area.

The fire in the valley, Burns said, changed from a fuel-driven fire to a wind-driven fire.

Westerly winds of 25 to 35 mph were forecast for the San Gorgonio Pass, with gusts to 50 mph Thursday, decreasing to 45 mph overnight, the National Weather Service said.

Firefighters established an anchor point in the area, Burns said, with hopes the fire “doesn’t come around behind them. But they’re going out into the wilderness, and once we get out into the wilderness, we can’t use heavy equipment, which slows down our progress of being able to get lines on the fire.”

He said smoke on Wednesday in the Morongo Valley prevented aerial tankers from dropping retardant there. And firefighters started out earlier than usual because they had stayed the night on the fire line. “We’re going to just keep our fingers crossed and see what happens today,” he said.

The fire was described as slow for both the area near Oak Glen and in the San Gorgonio Wildnerness.

The blaze, which has forced some residents out of their homes for seven days, is estimated to be fully contained Aug. 17. Containment is when firefighters create and hold a fire break around the perimeter of a wildfire. The break can be created by natural means, such as a stream or a river or roads and freeways, or by firefighters digging lines around the fire with bulldozers and hand tools.

The fire continued burning northeast into the San Gorgonio Wilderness, which has been closed to the public since Aug, 2. Burns said more firefighters might be brought into the wilderness area on Friday.

The South Coast Air Quality Management District extended its smoke advisory through Thursday for the San Gorgonio Pass, east San Bernardino Mountains, Coachella Valley and east Riverside County.