Photos

We triggered a small avalanche on a test slope at the ridgeline of the ramp. Wind was transporting the recent snow into drifts sensitive to human triggers. Photo: GNFAC

We snowmobiled up to 9,000' on Sawtelle peak, then skied to dig a couple pits. Our first pit was on an East aspect on a heavily wind loaded slope. The HS was 130cm (or 4.2 feet). There was 8" of new snow equal to 0.85" SWE, sitting over old consolidated snow that made up a slab over soft, weak facets about 50cm off the ground. We had ECTP24 x2 break on the old weak snow.... Photo: GNFAC

We snowmobiled up to 9,000' on Sawtelle peak on 12/23/23. The snow depth at 8,800' was 3-4 feet. Photo: GNFAC

A natural avalanche was seen yesterday,12/22, north of Cooke City that likely happened earlier this week. Photo: B. Fredlund

Large surface near Little Bear. Photo: JR Mooney

Skiers on 12/21 saw 2 old avalanches while skiing in the Divide Peak Cirque. These avalanches likely happened near the end of the last storm cycle, 12/9. 

From obs: "Saw evidence of two natural avalanches on southwest aspects (see photos). The age of these slides was hard to gauge based on our lack of recent snow."

Roller balls in Hyalite at 8000'. Photo: M. Zia

An avalanche along the divide between Muddy and Bear Creek. Avalanche was approximately 100 ft wide and 25 ft tall, breaking on facets just above a crust near the ground. Slide was clearly several days old, estimating it broke Friday, 12/15/23. Photo taken 12/19/23. GNFAC

Surface hoar is big and widespread along Buck Ridge. 12/19/23. Photo: GNFAC

Thin snowcover in 1st Yellowmule on 12/19/23. Photo: GNFAC

We dug 3 pits on or around the Ramp which is to the north of Bridger Bowl. One was SE facing, the other was E facing and our last was N facing. Depth ranged from 45 cm to 67 cm and all stability tests (6) had ECTN12-14. Photo: GNFAC

Like much of the advisory area, the snowpack in the Bridger Range remains thin. Photo: GNFAC

From email: "Just sharing a photo I took of some large surface hoar.  This was taken up in carrot basin in a spot that was especially bad, in the shadows sheltered by trees but adjacent to warmer sunny spot.  It didn’t look like this everywhere but it certainly was a common sight." Photo: J. Abate

Riders saw large surface hoar crystals while riding outside of Island Park. Photo. B.Schleicher

Skiers on 12/17 saw cracking while touring in Beehive Basin. Photo: E. Webb

Large Surface hoar found in open meadows in Lionhead on 12/15, 1+ cm. Photo: E. Webb

Big Sky Ski Patrol reported two natural avalanches seen today (12/15) in closed terrain. 

From email: 

"It looks possible that they released at two different times during the day today.....It looks to be the storm snow, which was sitting on lower-density snow at the old snow interface. That interface likely had a layer of faceted snow on top of the old, crusty snow. " Photo: Big Sky Ski Patrol

Natural avalanche in Lionhead that happened near the end of the last storm cycle (12/11) Photo: GNFAC

From obs: "We were ice climbing on Mummy 3 and 4 yesterday and as we looked across the valley to Mount Bole, we could see evidence of avalanche activity on the NE aspect of the peak. It looked quite big in length but could tell a depth from that far away." Photo: R. Dorn

Photo taken 12/14/23. Avalanche likely released the previous weekend, around 12/9/23. 

From obs: "We also saw some spectacular surface hoar- probably 1-2" tall in places with extremely sugary snow underneath" Photo: USFS Bozeman Snow Rangers