Avalanche Forecast
Regions: South Coast.
Confidence
Good
Weather Forecast
Unsettled conditions in the wake of Tuesday's storm system are expected to produce cloudy conditions and isolated light flurries with a few centimetres each day for the forecast period. The freezing level is expected to drop to and remain around 800 m, and the winds should remain light and variable.
Avalanche Summary
Reports from Monday are limited to occasional glide avalanche activity to Size 2.5 in the Coquihalla area. Natural avalanches probably occurred on Tuesday in response to heavy loading from snow, wind, and/or rain. Check out the telemarktips.com South Coast conditions forum for a report of a remotely triggered Size 3 slab avalanche on a north facing couloir in the east side of the Duffey Lake area on Sunday. The slab failed on basal facets and propagated 300m out of the couloir and wrapped around to the adjacent northwest.
Snowpack Summary
As of Tuesday morning, 15cm of new snow in the Duffey Lake area adds to the 40-70cm of snow that fell over the past week, while light rain fell in the Coquihalla area. The past week's snowfall overlies a predominately crusty interface, except north facing slopes at treeline and above where small surface hoar (5mm) may be found. Recent reports include hard but sudden compression tests results and a Rutschblock 4 whole block failure on this late-March surface hoar in the Duffey Lake area. In the north of the region, persistent early February layers linger deeper and could fail as large step-down slabs. Cornices are huge and potentially very destructive.
Avalanche Problems
Wind Slabs
Aspects: North, North East, East, South East.
Elevations: Alpine, Treeline.
Likelihood: Possible - Likely
Expected Size: 1 - 4
Storm Slabs
Aspects: All aspects.
Elevations: All elevations.
Likelihood: Possible
Expected Size: 1 - 5
Cornices
Aspects: North, North East, East, South East.
Elevations: Alpine.
Likelihood: Possible
Expected Size: 1 - 6