North Columbia

Buried weak layers will likely cause dangerous avalanche conditions to persist. Travel in avalanche terrain is not recommended.

On Tuesday, the avalanche cycle continued, with many large storm slab avalanches failing deep within the snowpack. They were generally 40 to 100 cm deep, on all aspects, and released within the various storm snow layers and on surface hoar.

On Monday, many small to large (size 1 to 3) storm slabs were triggered naturally and by riders.

A few large (size 2 to 3) avalanches released on facets above the melt-freeze crust in alpine and treeline terrain, localized to the Gold Range.

Anywhere from 20 to 50 cm of snow is expected to have fallen on Wednesday, with more on the way. The snow fell with strong southwest wind, forming even deeper deposits in leeward terrain.

The new snow will continue to overload a weak surface hoar layer and/or weak faceted snow found 50 to 100 cm deep. Surface hoar is most likely in tree openings sheltered from the wind, whereas faceted snow may be found in wind-exposed terrain into the alpine. Facets may be associated with a hard melt-freeze crust that formed in the middle of November.

Average treeline snow depths range from 110 to 170 cm, which tapers quickly at lower elevations.

Wednesday Night
Cloudy. 10 to 30 cm of snow. 40 km/h west ridgetop wind. Treeline temperature -2 °C. Freezing level 1500 m.

Thursday
Mostly cloudy. 5 to 20 cm of snow. 30 km/h west ridgetop wind. Treeline temperature -5 °C. Freezing level 1400 m.

Friday
Mostly cloudy. 4 to 15 cm of snow. 30 km/h west ridgetop wind. Treeline temperature -6 °C. Freezing level 700 m.

Saturday
Mostly cloudy. 5 to 20 cm of snow. 40 km/h southwest ridgetop wind. Treeline temperature -2 °C. Freezing level 1200 m.

More details can be found in the Mountain Weather Forecast.

• Travel in alpine terrain is not recommended.
• Remote triggering is a concern; avoid terrain where triggering overhead slopes is possible.
• Be aware of the potential for large, destructive avalanches due to deeply buried weak layers.
• Be cautious of buried obstacles, especially below treeline.