Tincan Trees

We toured up to treeline on Tincan and found alarmingly unstable avalanche conditions. So much so that we didn't feel comfortable traveling across the short ~ 30 degree slope that is required to traverse on the way up to Tincan Common. We triggered a small avalanche on a test slope and observed collapsing and whumphing between 2100' to 2300'. There was about 2' of wet and heavy storm snow from the past two days sitting on top of a layer of facets above an old ice crust. This is a bad slab/weak layer/bed surface setup that can cause very large avalanches. In addition, the skiing was really bad. With a 1-2" thick breakable crust on top and 6-24" of wet snow underneath. Above 2200' the skiing likely improves significantly but we had a bad feeling about heading up there today.

At the road elevation, there was a roughly 1" thick crust over about 5" of very wet snow. As we ascended the crust remained 1-2" thick and breakable until about 2200'. The wet snow underneath was about 24" deep above 2000' with a 3-4" thick layer of facets underneath sitting on top of an ice crust. We dug a set of pits at 2200' on a SE aspect and had propagating results in extended column tests (ECT P 1, ECT P 10) and in propagation saw tests (PST 22/100 END). The character of the failures was a sudden collapse, which is a sign of a persistent weak layer.