Storm Slabs
- Alta montaña
- Límite del bosque
- Bajo el límite del bosque
- Probabilidad
- Likely
- Tamaño
- 1–2
The weather broke for a few hours yesterday allowing for a look at storm totals at upper elevations and gave people a chance to test some slopes. Multiple human triggered avalanches size D1-2 were reported and observed involving the new snow. Settled storm totals of up to 20 inches were observed yesterday at 5000' in Gully 1. Storm totals gradually decrease with elevation and become more dense. Below 2000' there is only a couple inches of new snow and the avalanche problem changes from storm slab to wet loose (see problem 2).
Snowfall has been slowly accumulating since the 5th and has been coming in pulses, which has led to density changes within the storm snow that can act as failure planes. In addition to weakness within the storm snow, there is a concern that faceted snow exists on a crust at the interface of the new /old in some places. A D2 human triggered avalanche on the nose of Crudbusters shows a crown with a propagation length that indicates faceted snow at the interface rather than just a storm slab that needs time to settle. Details are not clear but it appears that at least one person of a group of 2 were caught and partially buried. More observations will be necessary to understand the new/old interface. But, what is easy to understand is that snow continues to accumulate and with no clear weather to allow the storm slab to settle and bond, human triggered avalanches will remain likely in terrain steeper than 32°. Wind loaded slopes and convex terrain features will be the most prone.
Conservative terrain choices and cautious route finding are recommended. Only expose one person at a time to avalanche prone slopes and maintain good communication within your group.
Skier triggered avalanche on the Nose of Crudbusters. 20 inches deep. SS-ASu-R3-D2-I
Photo: Oliver