The blaze has charred more than 18,000 acres since Friday as wooded slopes ignited amid hot, dry conditions that have plagued California for months. The fire was completely uncontained Sunday evening.
"There's no fire history in the past 100 hundred years. That's one of the reasons this fire's been able to burn so erratically," said Daniel Berlant, spokesman for the California Department of Forestry and Fire Protection.
In Southern California, about 4,000 visitors were evacuated Sunday from the Los Angeles zoo as a fast-moving brush fire burned nearby in Griffith Park.
Flames came within about 1,000 feet of a California condor enclosure in the park, forcing the relocation of the condors and two vultures, zoo spokesman Jason Jacobs said.
The fire had burned about 25 acres and was contained in under three hours, Los Angeles fire officials said. No injuries were reported.
Meanwhile, near Yosemite National Park, the wildfire led officials to order the evacuations of 195 homes under immediate threat. About 2,000 homes faced at least some danger from the fast-spreading flames, fire officials said. No injuries were reported.
State fire spokeswoman Karen Guillemin said the blaze was sparked by someone target shooting but would not elaborate.
Most of the evacuated homes are in the town of Midpines, about 12 miles from the park. The southern edge of the blaze was as little as two miles from Mariposa, a town of about 1,800 residents, Berlant said.
Some homeowners had refused to leave, and defied evacuation orders to stay and defend their properties.
"My house is about 100 yards from some fire right now and that's freaking me out," said John Romero, who answered his phone during a break from digging trenches and clearing brush with a little tractor.
Romero said his brother, Tony Romero, has an adjoining property with a 50,000-gallon swimming pool. He said they plan to pump the water from the pool to defend their homes if the fire advances that far.
Working in the smoky air has taken its toll. "I feel like I've smoked two packs of cigarettes, and I don't smoke," Romero said.
Mary Ann Porter, a nursing assistant who lives in Midpines, left her goats, chickens and dog when she evacuated Sunday morning. Porter, who lives with her daughter and grandchildren, said the family took pictures and some computer hard drives.
"One of the blessings of living up here is that you adapt and learn to accept things," she said, sitting a table reading a newspaper in the evacuation center in Mariposa.
To protect firefighters battling flames beneath power lines, electricity was cut to a wide area fire officials said.
James Guidi Jr., a spokesman for Pacific Gas & Electric, said the transmission line that fed power to Yosemite was destroyed in the fire on Saturday, and that firefighters cut the area's power grid for safety reasons.
Some park buildings were closed because of the power outage, but generators were still providing hotels, stores and other heavily used park facilities with electricity, park spokeswoman Julie Chavez said.
Mobile generators were being set up to restore power to the whole park and about 500 customers nearby by Monday evening. In all, about 1,000 customers in the area had lost power, Guidi Jr. said.
Officials warned motorists to stay off of Highway 140 between Mariposa and Yosemite this evening because of low visibility. This stretch of highway is often used by tourists heading into Yosemite.
"Because the ash and smoke is so heavy, there's zero visibility," said Wayne Barringer, a state fire spokesman on the scene.
Further north, in Siskiyou County, authorities reported the death of a second firefighter in as many days.
A firefighter believed to be a fire chief from Washington state died Saturday while scouting a blaze in Northern California, Siskiyou County Sheriff's Department spokeswoman Susan Gravenkamp said Sunday.
The 250-acre fire had prevented crews from recovering the body to make a positive identification, but several other firefighters identified the victim as Daniel Packer, 49, of Lake Tapps, Wash., Gravenkamp said.
Packer was the immediate past president of the Washington Fire Chiefs Association, according to Brian Schaeffer, assistant fire chief in Spokane, Wash.
On Friday, Washington state firefighter Andrew Palmer, 18, died after he was hit by a falling tree while battling another Northern California wildfire.