Firefighters gain an edge on wildfire in Yosemite National Park

Firefighters burn a fire break at the Rim Fire in Yosemite National Park in this Sept 1, 2013 handout photo. Firefighters in California gained ground the massive wildfire burning part of Yosemite National Park, although complete containment may be we
Firefighters burn a fire break at the Rim Fire in Yosemite National Park in this Sept 1, 2013 handout photo. Firefighters in California gained ground the massive wildfire burning part of Yosemite National Park, although complete containment may be weeks away, officials said. -- PHOTO: REUTERS

(REUTERS) - Firefighters in California gained ground on Monday against a massive wildfire burning part of Yosemite National Park, although complete containment may be weeks away, officials said.

Crews working through the night got an edge on the so-called Rim Fire, a 906 sq km blaze that has charred the California park's Northwest, said Andrea Capps, spokesman for the Rim Fire command center.

They connected containment lines near the fire's northwestern and western borders, where most of the 4,500 homes threatened by the blaze are located, she said.

The fire was 60 per cent contained by early Monday, a 15 per cent increase from the night before. "Last night is when it all really tied together," Ms Capps said. "It's looking really good over there right now. They're calling that containment line secure."

Despite the jump in containment, Ms Capps said fire analysts estimate that it could take until Sept 20 to contain the Rim Fire fully. Steep terrain and high, unpredictable winds will likely pose the main challenges in digging and burning containment lines around the blaze.

"The majority of the containment lines will probably be really strong by the middle, end of this week, but they just want to give themselves enough time to make sure it's fully contained," Ms Capps said.

Wet weather expected in the area on Monday raised hopes, but the possibility of thunderstorms kept officials wary.

"Rain is good, but the winds that come with the pressure changes with the thunderstorms could lead to some unpredictable (fire) behaviour," Ms Capps said. "We have had a few sprinkles this morning, and so we're all waiting to see what happens." While the majority of the fire was burning on Stanislaus National Forest, 24,367ha, or about 27 per cent, of the fire has crossed the Yosemite National Park border.

The massive blaze has scorched an area larger than many US cities and is the fourth-largest on record in California, burning more than 89,000ha over the past two weeks.

Over the past several years, wildfires in the US West have become increasingly frequent and at times deadly. Earlier this year, 19 firefighters were killed in a blaze in Arizona, and wildfires have raged in several states, including Nevada, Alaska and New Mexico.