Avalanche Forecast

A strong ridge of high pressure will keep the region dry and cold, with the potential for lingering valley clouds. The next round of snow is expected late Sunday night as a shift in the weather pattern will occur.

Friday night: Clear skies. Lingering valley clouds. Alpine temperatures around -15 C. Light northwesterly winds.

Saturday: Increasing cloudiness. Freezing level rising to 800 m. Alpine temperatures around -8 C. Light to moderate southwesterly winds.

Sunday: Snow 5-10 cm. Freezing level rising to 1100 m. Alpine temperatures around -4 C. Moderate to strong southwesterly winds.

Monday: Snow 15-20 cm. Freezing level rising to 1400 m. Alpine temperatures around -2 C. Moderate to strong southwesterly winds.

Wind slabs are still showing signs of instability on isolated features as human-triggered and natural avalanches have been reported thought out the region. A large avalanche (size 2) caught a skier by surprise on a steep lee slope, reloaded by the wind in the Selkirks. The failure plane was identified as a buried surface hoar layer from mid-February. Continued snow transport triggered a cornice fall which produced a very large slab avalanche (size 3) near London Ridge.

Persistent slabs were also observed lately, such as two very large avalanches (size 3) reported near London Ridge and in the Valhallas. They both occurred naturally on south-westerly alpine slopes. This evidence is showing that, with added load to the snowpack from the last weekend’s storm and continued winds, the mid-January weak layer began to "wake up". 

Recent cold temperatures and northerly winds have modified and transported the last storm snow (20-80 cm), creating heavily wind-affected surfaces in exposed areas and wind slabs in lee areas. Below ~1200 m, 10-20 cm of snow is now overlying a thick melt-freeze crust. 

Up to 80 cm is burying a weak layer formed in mid-February. This layer consists of surface hoar in sheltered areas, a melt-freeze crust at lower elevations, a sun-crust on steep solar aspects, and hard wind-affected snow in the alpine and exposed treeline. Reports suggest that in many areas, the recent snow is bonding poorly to this firm layer.

The mid-January surface hoar/crust layer is now down 50-150 cm in the snowpack. This layer has started to 'wake up' following last weekend's snowfall. 

• Recent wind has varied in direction so watch for wind slabs on all aspects.
• Be careful with wind slabs, especially in steep, unsupported and/or convex terrain features.
• Shooting cracks, whumphs and recent avalanches are strong indicators of an unstable snowpack.
• Be aware of the potential for large avalanches due to the presence of buried persistent weak layers.