08/29/2011 01:56 am ET Updated Oct 28, 2011

Yosemite Wildfire Spreads As Homes, Campgrounds Evacuated

By TRACIE CONE, Associated Press

FRESNO, Calif. (AP) -- Firefighters relied on a giant air tanker to make steady progress Monday against a five-day-old wildfire burning outside Yosemite National Park that has shut down one of the main roads leading into the park.

The fire was about one-third contained Monday and had not progressed much over night, though new areas might have to be evacuated.

The area of Old El Portal, a compound of private homes on national forest land, is under threat of evacuation. Campgrounds and trailer parks in the area have already been ordered closed, as well as a compound of about 70 homes leased to employees of Yosemite National Park.

But the fire has not caused any major problems at Yosemite itself, and the park's well-known stunning vistas have not been obscured by smoke, said park spokesman Scott Gediman.

The fire is burning along the Highway 140 corridor in the Stanislaus National Forest leading to Yosemite and has scorched more than 4,775 acres — or 7.5 square miles — since it began Thursday. It was sparked when a motor home caught fire.

The fire is an anomaly in what otherwise has been a relatively quiet fire season in California.

"This year we have not had very many large and damaging wildfires," said Daniel Berlant, a spokesman for the California Department of Forestry and Fire Protection. "The combinations of cooperation from the weather and aggressive initial attacks have kept them small."

But with a change in seasons coming that usually triggers higher winds, the most critical time is ahead.

"When summer ends, people think the danger goes down, but it's really the opposite," Berlant said.

The steep canyon terrain has made it difficult for firefighters on the ground. It has blackened the scenic Merced River Canyon to the top of the ridges on both sides of the canyon.

More than 800 firefighters have saved 70 homes, two commercial properties and 35 outbuildings, said Kass Hardy, a National Park Service fire spokeswoman. The school in nearby El Portal School has been closed because of the fire.