Yosemite National Park closes as wildfires scorch West Coast

One of America's most popular national parks, Yosemite, was closed Thursday as wildfires continued to scorch the West Coast, filling the air with toxic smoke and prompting evacuations in Southern California, officials said.

Dangerous air quality is expected in the park, which is spread across nearly 1,200 square miles in the Sierra Nevadas, for the next several days, the National Park Service said.

While firefighters have so far kept it from damaging a historic observatory in Angeles National Forest, the fire roared overnight toward Juniper Hills, an unincorporated community of about 400 homes in the San Gabriel foothills.

The Los Angeles County Sheriff's Department issued evacuation orders for Juniper Hills and other nearby communities Thursday afternoon.

Aeronautical engineer David Borden, president of the Juniper Hills Community Association, said he saw flames a couple of miles from his home early Thursday while he was preparing to go to work in the nearby city of Palmdale.

While speaking to a reporter Thursday afternoon, he was returning to Juniper Hills to see whether his home was still there.

The National Weather Service had issued flash flood watches across the state, he said, "so please be cognizant of that."