Avalanche Forecast
Regions: Glacier.
The February 22nd surface hoar layer is becoming more reactive as rising temperatures, wind and increased snow load encourage slab formation.
Weather Forecast
A frontal system crosses the province bringing mainly cloudy skies and isolated flurries with up to 5cm of accumulation. Ridge winds will be SW 25-35 km/h. The freezing level is forecast to climb as high as 1500m with an alpine high of -4 C.
Precipitation is expected to continue with the arrival of a pacific low on Friday with 15cm by Saturday.
Snowpack Summary
Strong southerly winds and warmer temperatures have contributed to the formation of a soft slab on top of the February 22nd surface hoar layer, buried 35-40cm. This layer is widespread up to 2300m. On solar aspects the surface hoar sits atop a crust. Incremental loading through February has created an otherwise benign mid-pack.
Avalanche Summary
An isolated natural avalanche cycle was observed in the highway corridor on the steep noth facing slopes of Mt Macdonald yesterday morning. Several small size 1.5 to 2.0 were observed, terminating near the beginning of the avalanche path fans. Numerous reports of small skier-triggered avalanches on the February 22nd layer in the surrounding areas.
Confidence
Intensity of incoming weather systems is uncertain
Avalanche Problems
Persistent Slabs
Feb 22 surface hoar is a persistent weak layer down 30-40cm that overlies a thick crust on solar aspects. It is easily triggered where soft slabs have formed, especially around tree line where the surface hoar is preserved and large.
- Watch for surface cracking and stiffer surface layers of snow.
- Convex features and steep unsupported slopes will be most prone to triggering.
Aspects: All aspects.
Elevations: All elevations.
Likelihood: Likely
Expected Size: 1 - 2