Fire officials and the Beaverhead County sheriff at noon on Saturday moved the evacuation status for areas of the Pioneer Mountains from “ready” to “set” as two wildfires show “extreme” fire behavior and with officials expecting similar conditions in the afternoon.

The evacuation status applies for Elkhorn Hot Springs and Maverick Mountain, including communities south to Shale Creek and Clark Creek on the north side of the Grasshopper Valley, officials said.

The Bobcat Lakes fire is seen Aug. 7 from a recon flight. Courtesy Inciweb

The Sand Creek fire was an estimated 8,890 acres and the Bobcat Lakes fire was an estimated 5,514 acres as of Saturday morning. The fires, which have burned for just over a week, now have 254 total personnel working them, along with nine engines, five crews, two dozers and a grader.

Crews discuss the day ahead on the Bobcat Lakes fire on Aug. 6. Courtesy Inciweb

Incident commanders Ian Quist and Brian Gorwitz said there were rapidly evolving conditions and periods of extreme fire behavior on Friday as the fire moved rapidly toward the south and east. Similar conditions are expected Saturday afternoon and evening.

They said firefighters are prioritizing structure protection and improving containment lines while continuing to lay hose near structures. A night shift was implemented Friday for additional structure protection as the fires approach private property and what officials said was other “critical values.”

Members of the Mormon Lake hotshots crew work to clear trees for a containment line for the Bobcat Lakes Fire along the Pioneer Mountains Scenic Byway in the West Pioneer Wilderness Area on Aug. 4. MEGAN NIELSEN, Montana Standard

Smokejumpers were inserted at the Clemow Cow Camp south of the Sand Creek Fire to protect remote cabins in the area. Firefighters also plumed “several miles” of hose along both fires. Officials said aerial operations will continue when weather allows.

Crews are expecting another day of hot and dry conditions, and the fires have not recovered much overnight in recent days, officials said.

A red flag warning is in effect until 9 p.m. Saturday, with relative humidity forecast to be between 8% and 15%, with westerly winds 5 to 15 mph and gusting up to 30 mph, according to the National Weather Service in Missoula.

There is also a slight chance that monsoonal moisture could spark some dry thunderstorms and erratic microbursts, the NWS said, but little rainfall is expected.

A road closure is marked on the road to the Lacy Creek Trailhead along the Pioneer Mountains Scenic Byway in the West Pioneer Wilderness Area on Aug. 4. Two fires, the Bobcat Lakes Fire and Sand Creek Fire, are burning in the West Pioneer Wilderness Area. MEGAN NIELSEN, Montana Standard

“Critical fire behavior weather is expected to persist with hot, dry, gusty winds and unstable atmosphere,” fire officials wrote in the morning update for the two fires.

There are widespread closures on the Beaverhead-Deerlodge National Forest and Wisdom Ranger District, including roads and campgrounds. The Pioneer Scenic Byway is also closed from Sheep Creek to Grasshopper Overlook for public and firefighter safety.

The cause of both fires remains undetermined.

Blair Miller is the managing editor of the Helena Independent Record and Montana Standard. Prior to that, he was the editor of the Montana State News Bureau, a reporter at the Daily Montanan and reporter, editor and photojournalist at news outlets in Denver, Albuquerque and mid-Missouri.