Alpine : Considerable
Treeline : Considerable
Below Treeline : Moderate
Travel Advisory : The recent storm has left a significant load of storm snow in lee alpine and treeline terrain. Some areas have been scoured down to the early December crust. The potential for skiers to trigger the persistent deep instability in the snowpack from shallow weak spots is an important point to consider. The natural avalanche cycle that occurred during the storm has left large debris beyond normal runout zones. Watch for easily triggered soft cornice noses that will continue to grow with the forecast precipitation and winds.
Avalanche Activity : Easily triggered size one soft slabs have been observed high in lee alpine start zones since the storm passed. At lower elevations, the new snow is loose and sluffing easily on variable old surfaces. A significant natural avalanche cycle up to size 3.5 occurred during the storm throughout the South Coast region. A size 3 accidentally skier-triggered avalanche on Sunday occurred in the ski area on a NE aspect after explosive testing and ski cutting failed to trigger any result. The crown was 3.75 metres deep and 75 metres wide and was determined to have failed on the Dec. 4th rain crust.
Snowpack : Moderate winds have created isolated soft wind slabs in high alpine terrain. Last week's storm snow is a deep and relatively uniform layer now that it has had time to settle. It is a significant load over the early December weakness that is being reported across the Pacific Northwest. The Dec. 4th facet-crystal and raincrust weakness is buried up to 3.75 metres deep in some lee features but on average it's 1.5-2.5 metres deep. In some wind-affected terrain you can still find it on the surface. Although this buried weakness has gradually been gaining strength, we continue to see significant results on this layer on all aspects. Snowpack tests from Tuesday saw moderate clean shears on the crust.
Weather : More wind, snow and some fluctuation in the freezing level is forecast to add another layer to the snowpack through the rest of the week.
