Avalanche Forecast
Regions: Sea To Sky.
Wind slabs and cornices are the main concern at upper elevations. A series of frontal systems are forecast to bring light to moderate amounts of snow in the coming days.
Confidence
Moderate - Forecast snowfall amounts are uncertain.
Weather Forecast
Tuesday Night: Flurries, accumulation 5-10 cm. Moderate southwest wind. Alpine high -5 C. Freezing level 500 m.
Wednesday: Flurries, accumulation 5 cm. Moderate to strong west wind. Alpine high -3 C. Freezing level 1100 m.
Thursday: Flurries, accumulation 10-15 cm. Light to moderate southwest wind. Alpine high -2 C. Freezing level 1000 m.
Friday: Flurries, accumulation 10-15 cm. Light to moderate and south and southwest wind. Alpine high -3 C. Freezing level 800 m.
Avalanche Summary
On Sunday there were reports of explosives controlled wind slab and storm slab avalanches to size 2 in the alpine. There was also a report of two size 3-3.5 naturally triggered deep persistent avalanches on a northwest aspects at 2600m. These would have run during or just after the storm on the weekend.
Snowpack Summary
Extreme southwest wind leading into last weekend has scoured windward aspects, formed loaded pockets up to 150 cm deep in alpine lees and contributed to rapid cornice growth. Light to moderate amounts of new snow are beginning to obscure this lingering wind effect. Below 1900 m, recent snow overlies a thick crust and tapers quickly with elevation.
Weak faceted grains and crusts near the base of the snowpack have not been an active avalanche problem recently, despite significant new snow loads. They are still on our radar, especially in inland parts of the region.
Terrain and Travel
- Carefully evaluate bigger terrain features on an individual basis before committing to them.
- Extra caution is needed around cornices under the current conditions.
- Pay attention to cornices and give them a wide berth when traveling on or below ridges.
- Recent wind has varied in direction so watch for wind slabs on all aspects.
Avalanche Problems
Cornices
Cornices have become noticeably larger and more overhanging the past week.
Aspects: North, North East, East, South East, West, North West.
Elevations: Alpine.
Likelihood: Possible
Expected Size: 1 - 2
Wind Slabs
Wind changing in direction from southwest to northwest has loaded new features which may be sensitive to human triggering.
Aspects: North, North East, East, South East, South, North West.
Elevations: Alpine, Treeline.
Likelihood: Possible
Expected Size: 1 - 2