The Rim fire, which is burning in and around the park, has scorched nearly 134,000 acres over the last eight days and is 7% contained.
Winds will be the biggest challenge for firefighters in the coming days. Ridge winds are expected to increase this afternoon and tonight, which could hamper containment efforts, said Kevin Durfee, a National Weather Service meteorologist in Hanford.
"It really looks like the weather is not going to be terribly cooperative in the next three days," he said.
Winds could gust up to 30 mph in the area around the fire, and will remain strong Sunday and Monday, said Drew Peterson, a National Weather Service meteorologist in Sacramento.
Temperatures are expected to remain steady at normal to below normal, which means no excessive heat to dry out fuels, he said. Humidity will be about 20% to 25%, he said.
"It could be drier, much drier than it is. The main thing they're going against is the winds," Peterson said. "If they can make it until Tuesday, it looks like conditions will be better."
On Sunday, as nearby Groveland breathed a collective sigh of relief — the town was plastered with signs to firefighters reading "Thank You! We love You" — Tuolumne City, about 45 minutes away, became the latest Sierra town in the line of fire. Black Oak Casino was evacuated. The tourists left, but then the hotel's 148 rooms immediately filled with emergency workers. In nearby Sonora, the smoke was so thick that the local Wal-Mart closed.
Firefighters were digging trenches with bulldozers as well as hand-digging lines to try to hold the fire at least a mile away from Tuolumne City, the way they did in Groveland.
It is one of California's largest fires in recent history.
"It's the worst one I've seen in 23 years. It's even worse than in 1987 when parts of Yosemite looked like a moonscape," said Groveland Hotel owner Peggy Mosley.
Her inn was filled with national news crews and she winced as they headed toward Yosemite instead of Tuolumne City. The tourist mecca of Yosemite Valley is open and the skies are clear, but the fire has crossed into the remote country on the northwestern side of the park, leading to headlines linking the national park and fire.
"Yosemite is an international destination and people don't understand the distance," she said. "This morning I got a call from someone in Switzerland saying, 'So Yosemite burned down?'"