A large cornice, well below treeline on the Baldy Trail, broke free as skiers toured past. The cornice was dripping with water, a strong sign that it's losing internal strength. Although this was low consequence terrain, it illustrates the problems we'll encounter at higher elevations with warmer, spring weather. Photo: C. Kautz
11-12
GNFAC Avalanche Advisory for Sun Mar 11, 2012
Snowpack and Avalanche Discussion
The Madison and Gallatin Ranges, the mountains around Cooke City, the Lionhead area near West Yellowstone and the Bridger Range:
Solar radiation and warm temperatures have affected slopes with a southerly aspect, while shady slopes on the northern portion of the compass continue to hold sections of cold and sometimes powdery snow. Beneath the surface however, two problematic weak layers lurk on all aspects – a layer of near surface facets buried 2-3 feet deep and a layer of depth hoar near the ground.
This avalanche in the second yellowmule off Buck Ridge was likely triggered by a snowmobiler today. It was on a steep wind-loaded slope (northeast facing) and the avalanche propagated a few hundred feet wide. A layer of small faceted crystals was the likely culprit. This layer is on many slopes. Photo: TJ Krob
The hard, wind slab debris hit a steep transition and did not travel far. This slide was likely triggered by a snowmobiler. Photo: TJ Krob
GNFAC Avalanche Advisory for Sat Mar 10, 2012
Snowpack and Avalanche Discussion
Wet snow avalanche danger
Snow Rangers in the Cooke City area observed many natural slides that occurred over the past few days. This slide occurred on a heavily wind loaded slope and probably failed on a layer of near surface facets formed in the middle of
February. Photo Adam Norlander
This slide occurred on Fan Mountain near Big Sky. A natural cornice drop was likley the trigger. Photo MW
This slide was triggered by a cornice dropping onto a thinner, more faced part of the slope. The slope was heavily wind loaded. Photo: J. Barkhausen