Avalanche Forecast
Regions: South Columbia.
There is uncertainty with the reactivity of several buried weak layers. Best to adopt a conservative approach while the snowpack adjusts to the increased load from recent snowfalls.
Confidence
Moderate - Uncertainty is due to field data and reports showing a wide variation in conditions throughout the region.
Weather Forecast
Saturday Night: Flurries, accumulation 1-5 cm, alpine temperature -8, moderate northwest wind.
Sunday: Sunny with cloudy periods, alpine temperature -9, moderate northwest wind.
Monday: Mix of sun and clouds, alpine temperature -7, moderate north wind.
Tuesday: Mix of sun and cloud, alpine temperature -8, light northwest wind.Â
Avalanche Summary
Reports from Friday indicate skier triggered and natural storm slab avalanches to size 1-2 within the storm snow. Additionally there were explosives controlled avalanches to size 3 along the Trans Canada highway corridor. On Thursday there were reports of a few explosives triggered size 2.5-3 storm slab avalanches on southeast aspects in the alpine. There were also a few reports of persistent slab avalanches failing on a layer of surface hoar (down 60-80 cm) at treeline elevations.Â
Snowpack Summary
20-40 cm of new snow from the past few days has covered a layer of feathery surface hoar that has been found at all elevations in some parts of he region. A thick layer of faceted crystals, previously wind-affected surfaces, and/or surface hoar in sheltered areas (around treeline and below) is now 40-80 cm below the surface.
An additional layer of surface hoar may be found in sheltered areas around treeline down 60-100 cm. In some areas this may sitting on a thin crust.
A variety of crusts from late October are buried deeper in the snowpack. Total snow depths range from 140-200 cm around tree line.
Avalanche Problems
Storm Slabs
20-45 cm of new snow accumulating over the past 48 hours has formed a reactive storm slab. In some areas this may be sitting on a layer of weak surface hoar.
Aspects: All aspects.
Elevations: All elevations.
Likelihood: Possible - Likely
Expected Size: 1 - 2
Persistent Slabs
A surface hoar/crust layer down 60-100 cm has become reactive with the recent storm snow. This layer is most likely found in sheltered openings around treeline and below.
Aspects: All aspects.
Elevations: All elevations.
Likelihood: Possible
Expected Size: 1.5 - 3