Idyllwild, a town of 4,000 people living in the mountains 10 miles southwest of Palm Springs, is directly in the path of the wildfire.
"Everybody's known that if the fire ever came over that ridge, Idyllwild is probably toast," resident Malcolm Oakes said.
Seven homes have already been destroyed in the fire, which is being battled by more than 3,300 firefighters, 17 water-dropping helicopters and 10 air tankers.
Forest service officials are keenly aware that Idyllwild is facing an existential crisis.
"Embers get into the column and can drop anywhere," said Incident Commander Jeanne Pincha-Tulley. "For the next two days, it is predicted to go right over the top of this town."
Most of the residents of Idyllwild have already been evacuated.
Resident Claudia Posey said the threat is hard to even comprehend.
"I have seen it on TV a bunch of times and it was hard to relate to, and now it just feels indescribable," she said.
The Mountain fire, burning since Monday, was just 15 percent contained Friday. Some evacuations were lifted for residents of Apple Canyon and Bonita Vista, but remained in place for Fern Valley and Trails End at Morris Ranch Road, as well as Idyllwild, Forest Service officials said.