Tincan Trees – Storm Day with High Avalanche Danger
Several 2' thick storm slab avalanches were triggered by skiers today in the Tincan Trees. Including one triggered remotely from our party.
|Cracking (Shooting cracks)?||Yes|
One could add "Rapid Loading" to this list of obvious signs. A lot of snow has piled up today and is very touchy.
All the human triggered avalanche activity observed was on short slopes in "small terrain". One of these piled debris on the bench below enough to bury a person. In "larger terrain" these 2+' storm snow slabs would be large and dangerous.
Collapsing (whoomphing) and shooting cracks were the norm.
Snowing 2" an hour for the better part of the day.
Obscured skies, no visibility.
Winds were light from the East near the top of treeline and light from the North along the Pass.
Temperatures were in the upper 20's F and climbing slightly during the afternoon.
Treeline: 24" of new medium density snow (and counting)
Parking lot: 20" of new higher density snow (and counting)
Instability within the snowpack is confined to the new snow and old snow interface. The avalanching and cracking was occurring in the old faceted snow that sits just under the new snow. See photo. In areas with no old faceted snow (where the pre-existing surface was hard) the failure point was in the new snow just above the old hard surface.
Regardless of the weakest layer being either above or below the new/old snow interface - too much snow too fast = avalanche activity. Great to see so much snow out there!