Avalanche Forecast
Regions: East Island, North Island, South Island, Vancouver Island, West Island.
Heavy snow and rain have impacted an unusually cold and dry snowpack. Raise your guard anywhere the storm snow remains dry, it is likely bonding poorly to the underlying surface.
Confidence
Moderate
Avalanche Summary
On Thursday, our Field Team skier triggered several wind slabs (size 1-2) from alpine and treeline terrain near Mount Cokely. Read more in this MIN.
We suspect a widespread natural avalanche cycle occurred on Friday with heavy loading from snow, rain and wind.
Looking forward to Saturday, the avalanche problem is likely to present as wet loose avalanches in steep terrain. If the storm snow remains dry, storm slabs may be reactive to human triggering.
Snowpack Summary
Rain has impacted the snowpack in most areas. Dry snow may prevail in the alpine in the higher peak and will have been redistributed by strong southerly winds.
A weak facet/crust layer can be found down 50 to 100 cm. The remainder of the snowpack is strong, with numerous hard melt-freeze crusts.
Treeline snow depth ranges from 100 to 180 cm. Snow depth diminishes rapidly at low elevations where there has been more rainfall.
Weather Summary
Friday Night
Cloudy with rainfall, 5 to 15 mm. Alpine wind southwest 30 to 50 km/h. Treeline temperature 3 °C.
Saturday
Cloudy with light rain. Alpine wind 10 to 30 km/h from the southeast. Treeline temperature 3 °C.
Sunday
Cloudy with mixed precipitation, 2 to 15 cm of new snow accumulation at higher elevations. Alpine wind southwest 30 to 50 km/h. Treeline temperature 1 °C. Freezing level 1500 m.
Monday
Cloudy with mixed precipitation, 5 cm of new snow accumulation at higher elevations. Alpine wind southwest 15 to 40 km/h. Treeline temperature 3 °C. Freezing level 1500 m,
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Don't be too cavalier with decision making, storm slabs may remain sensitive to human triggering.
- Stay off recently wind loaded slopes until they have had a chance to stabilize.
- Avoid terrain traps such as gullies and cliffs where the consequence of any avalanche could be serious.
Avalanche Problems
Storm Slabs
Dense storm snow overlies light, low-density snow and may remain reactive to human triggering, particularly in wind-loaded terrain.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood: Possible - Likely
Expected Size: 1 - 2.5
Persistent Slabs
A weak layer of facets overlying a crust exists down 50 to 100 cm. This layer is most likely to be an issue in wind-loaded, high alpine terrain where the recent storm snow remains dry.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood: Unlikely - Possible
Expected Size: 1.5 - 3
Loose Wet
Where the snowpack is wet from recent rain, wet loose avalanches may be triggered in steep terrain, and could run easily on the underlying crust.
Aspects: All aspects.
Elevations: All elevations.
Likelihood: Possible
Expected Size: 1 - 2