BIG TIMBER, Mont. (AP) - Firefighters made some headway against an enormous wildfire that chased hundreds of residents from their homes, but officials cautioned on Tuesday that it was far from being contained.

The fire, in south-central Montana, has burned 26 homes, blackened more than 280 square miles and is classified as the nation's No. 1 firefighting priority.

"We're still working on this thing on all fronts," said Dixie Dees, a fire information officer.

Crews were able to build additional fire lines around the blaze Monday when the wind didn't pick up as feared. Eight airplanes dumped 14,000 gallons of fire retardant, and a fleet of about seven helicopters dumped 190,000 gallons of water, said Allison Jackson, another fire information officer.

The fire, started by lightning on Aug. 22, was estimated at 25 percent contained Tuesday, authorities said.

About 265 homes were evacuated in just a few hours Sunday night on the western flank of the fast-moving blaze, said Kelly O'Connell, Sweetgrass County disaster and emergency services coordinator.

Fire officials feared that wind and higher temperatures this week would create extreme fire conditions.

Firefighters in Washington state were still battling fires that have charred more than 270,000 acres, or nearly 422 square miles.

"Red flag" warnings for low humidity and gusty wind were in effect Tuesday in north-central Washington for a group of wildfires that had blackened more than 32,000 acres, or about 50 square miles, in a wilderness area north and south of the town of Mazama. Part of the fire had crossed the border into Canada, covering nearly 4 square miles between Manning and Cathedral provincial parks, about 125 miles east of Vancouver.

Up to two dozen new wildfires started by lightning in northeast Nevada on Sunday and Monday had exploded across more than 117,000 acres, or 183 square miles, of rangeland by Tuesday.

"Resources are stretched thin all over the West and it's going to be a big problem getting help," fire information officer June McMillen said from Elko, Nev.

The three biggest Nevada fires threatened scattered ranches and had destroyed at least one barn, but no housing areas were in danger, McMillen said.

In Southern California, a wildfire raced over at least 1 square mile of steep, rugged terrain in the Los Padres National Forest, prompting hundreds of campers and fly fishermen to evacuate a recreation area. The fire broke out Monday about 10 miles northwest of Castaic. There was no immediate threat to homes.