According to an update from the Custer Gallatin National Forest, fire crews gained a lot of ground on the Porcupine Wildfire on Friday.

On Saturday. firefighting crews continued working to mop up and extinguish any hot spots on the wildfire, now estimated at 680 acres.

On Friday and Saturday, fire activity was minimal and the cold front moving in is expected to help crews gain even more ground.

The fire is currently at 50% containment with full containment estimated by Sunday. Pre-evacuation notices are still in effect for the time being. Resources on the fire Saturday included 2 engines. and air resources were on standby. The cause of the Porcupine Wildfire is still undetermined.

The fire is located about one mile south of Highway 191 and Highway 64 junction near Big Sky by the Porcupine Trailhead. It was initially reported around 1:00 p.m. on Thursday, November 5 and is located on the east side of the Gallatin River burning in meadows and timber on both State and Forest Service land. No structures were damaged or lost.

It was originally suspected that the Porcupine Wildfire was started from a spot fire or embers from the Porcupine Prescribed Burn that was occurring in the same area.

Crews working on the prescribed burn immediately responded to the wildfire to begin suppression efforts and additional resources were ordered. Given the distance between the prescribed burn and the wildfire, a fire investigation is underway to determine the cause.

For the latest information and updates, visit the Custer Gallatin National Forest website or Facebook page.