After battling the Rim Fire in and around Yosemite National Park for nearly two weeks, firefighters were buoyed to see the blaze slow for the second day in a row — but they have not yet declared victory.

The fire spread at about 300 acres an hour Thursday, though planned burnouts in Yosemite pushed numbers higher in the afternoon after the number of acres barely budged overnight.

By sundown, the inferno reached nearly 200,000 acres to become the fifth-largest blaze in 81 years of California recorded fire history, surpassing the 2007 Witch Fire in San Diego County, which destroyed 1,650 structures and killed two people.

But the growth was still far below the explosive rate seen last week, when the fire was spreading at 3,000 acres an hour during its apex. Fire containment grew to 32 percent, up from 30 percent, and the evacuation advisories were lifted Thursday for nearby Tuolumne City and two small communities: Soulsbyville and Willow Springs.

Cal Fire says the cooling temperatures, rising humidity and constant work from 4,900 firefighters to dig dirt lines to contain the fire all combined to help slow the flames.

Still, temperatures were expected to rise again Friday, with the humidity forecast to drop, said Cal Fire spokesman Daniel Berlant. That would make it easier for the flames to spread and could exhaust firefighters in the field, he said.

Dick Fleishman, a spokesman for the U.S. Forest Service, which is leading the response with Cal Fire, said all it would take for the fire to explode again is to reach the base of a hill, where it can race upward or into a canyon that would act like a chimney.

“That potential is still out there,” Fleishman said. “There’s a lot of work that still needs to be done.”

The estimate for full containment of the blaze was pushed back from two to three weeks.

The Rim Fire is named for the Rim of the World vista point off Highway 120 west of Yosemite, close to where the blaze first sparked. It now has cost $47 million to fight.

The Yosemite Conservancy announced it was launching a fundraising campaign to help restore trails and lost habitat in the tens of thousands of acres in the park that have been burned since the fire began on Aug. 17.