Quick report
- Red Flags
- Recent Avalanches
Photos are of two old crowns from Maybird Gulch. I could not find these avalanches previously reported, and they seemed to be slabs of wind-drifted snow, likely from cross-loading from winds from the west.
Overall, I am feeling confident in the direction our snowpack is heading. For the past week, I have been finding a generally stable snowpack on north aspects, with the avalanche issues involving wind-loading. There is a layer of facets on top of a crust on primarily east and southeast aspects, but in several pits on these aspects, I have only found a few where I can get a full propagation with an extended column test. I do not think this PWL layer on solar aspects will linger all that long as the layer of facets does not look especially weak.
Snowpack
- Instability Comment
- <p>We encountered some wind-drifted snow underneath Wednesday's 15-20 cms new snow. One on pit on a NE aspect at 9,700', we got full propagation (ECPT21) with also clean, moderate shovel shears. This was failing in a layer of graupel down 55 cms, with a 25 cm 1F hard wind slab on top of the graupel layer. On other slopes that were not recently wind-loaded, extended column tests were ECTN with Q3 poor quality shears.</p> <p> </p> <p>The layer of graupel down 55 cms is likely from snowfall Sunday morning. Graupel is not a persistent weak layer, but it can often take several days to stabilize. There are several different storm interfaces from this past week, with various layers of graupel. There is no pattern to where graupel layers are located, and graupel can often be found below cliff bands where it pools. </p> <p> </p> <p>Slopes with recent wind-loading are the most likely slopes for avalanching on a layer of graupel.</p>
~20 cms of dense graupel that made for superb travel and riding conditions. Some slopes got enough sun to be crusted on Friday, and some greenhousing creating damp surfaces. Given how weather varied, there will likely be no pattern for determining what slopes will be crusted.