Photos

On the way into and in Tepee Basin, we saw widespread and large surface hoar on the snow surface. Photo: GNFAC

Spent the day up near ski hill with West Yellowstone Avalanche Fundamentals course.

We dug various pits @ 8000' below ski hill and found HS 85-55cm on NW-NE aspects.

The snowpack structure there had weak snow at the ground capped by a stout ice crust with faceted snow over the crust beneath the recent snow.

We recorded ECTP4, ECTP11, ECT20 & a few more propagating results on facets above the crust.

Photo: S. Regan

 Widespread, intact, surface hoar was seen at Lionhead. Photo: S. Regan

Got a view of the bowls behind maid of the mist and above twin falls today. Multiple natural wind slabs, up to size 2, on E and NE aspects, roughly 9500 ft. SS-N-R2D2-I.  My guess is they are roughly 48 hrs old.

A skier triggered avalanche on the SE face of Mt. Blackmore. Crown is marked.

Doug investigating the basal facets after an ECT failed upon isolation (ECTPV)

Photo: GNFAC

On 12/11, skiers noticed this recent D2 avalanche on the E aspect of Blackmore. As they skinned up the SE meadow, they experienced three audible whumpfs. Photo: Eric H

From obs: "Yesterday 12/10/2023 at 0900, my climbing partner and I observed a clear crown line that extended throughout much of the east/ north east aspect of the bowl on Elephant Mountain. "

Alex Marienthal found unstable snow in Beehive at 8,700' on a SE facing slope. Test scores were ECTP 12, 5, V. All breaks were on the large facets in the middle of the snowpack. We also had lots of whumpfs, which is the snow collapsing under our body weight, and a very bad sign. 

From IG: Natural activity in Beehive Basin

From IG: "Natural activity in Beehive Basin"

A recent skier triggered avalanche at Bridger Bowl in Lower Super couloir.

Riders in Taylor Fork saw natural avalanches on Saturday, 12/9 Photo: W. Sanzone

Riders in Taylor Fork saw natural avalanches on Saturday, 12/9 Photo: W. Sanzone

Skiers saw widespread cracking while skiing on 12/09. Photo: C. Von Avis

From obs: "Several small whoomphs were observed in the shallower, bushy snow at lower elevations, and we had a massive (~100-foot propagation) whoomph on the ridge proper where the cornice met the ridge. Accompanying those whoomphs, we observed shooting cracks at multiple low-angle locations." Photo: J. Krause

From IG on 12/10: "2 slides we triggered remotely in tepee yesterday"

From obs: "Felt wumphs every few steps and had around 30 foot shooting cracks in meadows and on ridgelines."

From obs: "Windier then I expected today at me d elevations adjacent to Bridger ... Photos show lots of wind transport during the day. Felt a few collapses while skinning."

From obs: "Windier then I expected today at me d elevations adjacent to Bridger ... Photos show lots of wind transport during the day. Felt a few collapses while skinning."