PORTLAND (AP) — A wildfire that started in August has made its way into Crater Lake National Park.

The fire has crossed the southern boundary of the park, the U.S. Forest Service said Thursday.

The fire was named Middle Fork. It had nearly doubled in size in a day and was burning on nearly 14,000 acres Thursday.

Fire spokeswoman Ada Takacs said crews plan a second base camp at the park’s south entrance.

No park closures have been announced, but visitors are being told to expect heavy smoke and possible delays as crews and equipment move through the area.

Cooler temperatures and damper conditions are expected.

Elsewhere in Oregon:

• The Gnarl fire on the east side of Mount Hood was on 2,375 acres and threatening historic structures including the Cloud Cap Inn and the Tilly Jane Campground.

About 50 structures are threatened. Federal authorities said that includes 18 homes that have been evacuated and 18 more where residents have been put on notice they may have to leave.

• Parts of Oregon 138 in southwest Oregon remained closed Thursday by the Rattle fire near Glide, which was at 11,200 acres.

• In the Cascade Range between Eugene and Klamath Falls, the Royce Butte fire was at about 380 acres near Crescent, and firefighters said favorable weather conditions allowed them to establish a perimeter around the fire.

Oregon 58 was reopened, though speeds were reduced because of the smoke. And residents of the area were allowed to return to their homes — with the warning they should be ready to leave again.

• North of Medford, the Oregon Parks and Recreation Department said it had closed Tou Velle park so that firefighters could use it for a camp.