Persistent Slabs
- Alpine
- Treeline
- Below treeline
- Likelihood
- Possible
- Size
- 3
A dangerous structure of a strong slab of snow over a persistent weak layer of faceted snow down near the ground exists on mid and upper elevation aspects facing northwest, through north, and east. Although this weak layer has become mostly dormant over the past week, several days of southerly winds over this past weekend and through Tuesday have created dense wind slabs on the aspects where this weak layer can be found.
The most recent avalanche activity I am aware of that failed on this layer of weak snow down near the ground occurred overnight Saturday in South Monitor bowl along the Park City ridgeline (observation) in the Salt Lake mountains. This slope has avalanched this season (known as a "repeater"), with weak faceted snow remaining in place on the bed surface. The slope had filled in again from wind-loading, and naturally avalanched, perhaps from a cornice fall.
Although the likelihood of triggering one of these large avalanches reduces each day, there remains a possibility. Slopes that have a thinner and weaker snowpack are the most susceptible, this includes:
- steep rocky terrain;
- repeater slopes that have already avalanched this season (i.e. South Monitor).
If you choose to enter the terrain where this avalanche problem exists, consider the consequences of triggering one of these large avalanches.
Danger Trend: Steady to Decreasing
