Avalanche Forecast
Regions: Coquihalla, Harrison-Fraser, Manning, Skagit.
Lingering wind slabs may remain reactive to human triggers on a variety of aspects at treeline and above.
Avoid travelling on slopes below cornices.
Confidence
Moderate
Avalanche Summary
No new avalanches were reported in this region on Monday.
On Saturday, explosive avalanche control work resulted in numerous very large avalanches. They included storm, persistent, and deep persistent slab avalanches and were size 3-4. They initiated on a variety of aspects in the alpine.
Snowpack Summary
Cornices are large and may fail with daytime heating.
Sun crust on sunny aspects. Up to 100 cm of snow last week and shifting strong winds formed wind slabs on a variety of aspects at treeline and above. These slabs are sitting on either hard surfaces or small facets.
A crust formed in mid-January can be found down 90 to 130 cm. In areas around the Coquihalla, facets can be found sitting on the crust. This layer is of greatest concern with large triggers, such as a cornice fall, or by first triggering a smaller avalanche that could step down to this interface.
Weather Summary
Tuesday Night
Mostly clear skies / Light south ridgetop wind / Low temperature at treeline -12 C / Freezing level valley bottom.
Wednesday
Mostly sunny / Light southeast ridgetop wind / High temperature at treeline -1 C / Freezing level 1300 m.
Thursday
Sunny / Light southeast ridgetop wind / High temperature at treeline -2 C / Freezing level 1100 m.
Friday
Cloudy with flurries; 3-5 cm / Light southeast ridgetop wind / High temperature at treeline -4 C / Freezing level 800 m.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Be especially cautious as you transition into wind affected terrain.
- Recent wind has varied in direction so watch for wind slabs on all aspects.
- Avoid shallow snowpack areas, rock outcroppings and steep convex terrain where triggering is most likely.
- Avoid exposure to slopes that have cornices overhead.
- Be alert to conditions that change with elevation and sun exposure.
Avalanche Problems
Wind Slabs
Wind slabs may remain reactive on a variety of aspects at treeline and above.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood: Possible
Expected Size: 1 - 2.5
Cornices
Cornices are large and may fail with daytime heating. Cornice failures act as heavy triggers and can trigger large avalanches on slopes that a single rider would not trigger.
Aspects: North, North East, East, South East, North West.
Elevations: Alpine.
Likelihood: Unlikely - Possible
Expected Size: 1.5 - 3
Persistent Slabs
A crust formed in mid-January can be found down 90 to 130 cm. In areas around the Coquihalla, facets can be found sitting on the crust. This layer is of greatest concern with large triggers, such as a cornice fall, or by first triggering a smaller avalanche that could step down to this interface.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood: Unlikely
Expected Size: 1.5 - 3