With this area east of San Diego getting a break from California's heat wave Wednesday, firefighters were able to make progress against a wildfire that triggered evacuations as it crept toward rural communities.

Crews reported that the more than 25-square-mile blaze in the Cleveland National Forest was 18 percent contained Wednesday morning, up from just 5 percent containment Tuesday.

"The temperatures were a little cooler. The winds were calmer. Humidities were still on the high side," said Roxanne Provaznik of the California Department of Forestry.

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The small community of Carveacre was evacuated because of the more than 16,000-acre wildfire, and residents of a half-dozen other small clusters of homes were on notice they also might be told to leave.

Authorities were investigating the cause of the blaze, which may have been started Saturday by an abandoned campfire set by illegal immigrants.

In counties northwest of Los Angeles, crews were battling two lightning-caused wildfire clusters in Los Padres National Forest, each covering about 2,200 acres or more than 3 square miles.

East of Los Angeles, firefighters on Tuesday night contained a fire in Joshua Tree National Park that had burned 993 acres, or 1.6 square miles. Two homes were destroyed, fire spokesman Dennis Cross said.

In northeastern Oregon, firefighters said 20 buildings were at risk Wednesday from a rangeland fire that had covered about 10,000 acres, or 15 square miles, on the southern edge of the Wallowa Mountains.

In Oregon's largest blaze, 60,000 acres, or 94 square miles, of rangeland had burned east of Steens Mountain in the southeastern part of the state. Firefighters said they were trying to protect features in a wilderness study area and six threatened structures, and they didn't expect containment until the end of the week.

In western Montana, a 500-acre blaze east of Florence had destroyed one mobile home and led to the evacuation of about a dozen other homes, fire officials said Wednesday. Residents of a dozen other homes were warned that they, too, might need to evacuate.