On Thursday 11/21 skiers at Bridger noted: "...some activity (D1-D2) isolated to the new snow around rock features and ridgetops that were wind-affected..." Photo: G. Antonioli
From obs.: "I went skiing at Bridger today,... There was 4-5” of new snow, which was sitting on a firm surface. The wind had done some work, and I was able to break off a few shallow (6”) wind slabs in the first 100 feet or so off the ridge." Photo: A. Schauer
A skier on Saturday (11/16) took the time to dig a quick pit about 200' below east ridge of Mt Blackmore. He found about 2.5 feet of snow with a few crust layers. Photo: K. Stewart
From Doug Chabot:
I went ice climbing in Flanders and got hit with a graupel storm (0830) which avalanched off the climbs on east-facing slopes for over an hour. It was pretty spectacular and we found knee deep graupel (small, ball-bearing like grains) 200 vertical feet from the bottom of the cliffs. The climbs that we saw this on were Big Sleep, Bobo Like and Killer Pillar. The snow appears to be sliding on a razor thin ice crust under the 3" of new snow that fell last night, which was dense (estimated 15%).
I dug a hand pit to the ground and found 2' of mostly solid snow (no obvious facets) with a couple ice crusts in the upper third. A CT cut with a ski pole yielded no fractures. Elevation 8,000', east aspect.
From obs: "Went for a tour up to Hyalite Basin. No recent sightings of avalanche activity in the basin. There was substantial wind effect on East aspects at 9,000 feet including a dense 3 inch wind layer that was present up to the saddle, which did not propagate in our ECT. We observed a crust layer on south aspects at 7,000 which likely formed before the most recent snow." Photo: Tommy Saulnier
From an email: "I observed a wet loose avalanche that most likely occurred yesterday afternoon. Occurred at an elevation of 8,900' on a WSW aspect, along the runout of a chute sometimes referred to as "the gem". It wasn't very large, but it ripped out to the ground in sections and looked like it could do some damage if caught off guard. I assessed the snowpack next to the small slide, and found a snowpack of only 30 cm composed of facets from 0-14 cm above the ground (F hardness), a crust of large bonded grains from 14-16 cm above the ground, small facets / rounding facets from 16-23 cm above the ground, a rain crust from 23-27 cm that blended into wet snow on the surface becoming slabby in the afternoon sun."
Outside advisory area, but seemed relevant to report a climber triggered avalanche today (12/11/2019) at around 9000 ft, on a 35 degree slope on a NW aspect. Solid size 2, triggered roughly 15m below the crown (depth 20-40 cm, width 15m) Failed on a density change below a fresh windslab, ran around 100m and deposited 1m of debris towards the bottom of the runout. HS-AF-D2/R3-I. No injuries.
These feathery surface hoar crystals were buried under 5" of snow last night up Hyalite. These weak grains may become a problem with additional load. Phoro: B. VandenBos
Natural wind slab avalanche on the N face of Mount Blackmore on 11/10/2019.
From email: "Noted recent activity on the N face which likely happened yesterday during the storm; upper half of the avalanche and crown had been scoured by wind, but the toe of the debris was still visible and had traveled quite far"
