Persistent Slabs
- Hochgebirge
- Waldgrenze
- Unterhalb der Waldgrenze
- Wahrscheinlichkeit
- Likely
- Größe
- 3
Yesterday Nikki and I went hunting for old, weak, faceted snow near the ground on Peak 10,420 in Big Cottonwood Canyon. We easily found it on any slope facing northerly or east at mid and upper elevations. This layer of facets has a dense slab 2-4 feet thick on top of it. The combination of new snow or wind loading every few days has added stress to this persistent weak layer and kept it unstable and dangerous.
Recent avalanches and collapsing are clear warning signs to avoid terrain where this problem exists. Drew and his partners yesterday skied into the Mill Creek drainage where they didn't see any obvious signs of instability; however, the simple existence of this layer kept them on low angle slopes.
Picture below shows terrain to avoid. If you look closely you may see a faint avalanche crown in the shade.
THE GOOD NEWS: Southerly facing terrain will have good turning and riding conditions today where you don't have to deal with this avalanche problem.