Avalanche Forecast
Regions: Birkenhead, Duffey, South Chilcotin, South Coast Inland, Stein, Taseko.
Big scary avalanches!
Warm temperatures and sun further destabilize the already spicy snowpack conditions. Stay disciplined and resist venturing into consequential terrain.
Confidence
Moderate
Avalanche Summary
Large, scary persistent slab avalanche activity continues to be reported daily. On Wednesday and Thursday, solar-triggered naturals were reported size 2-3 in the alpine, and remotely-triggered slabs were reported size 2-2.5 at alpine and treeline elevations. Many were triggered by riders from hundreds of meters away, failing on a layer of surface hoar buried 50 to 90 cm deep, resulting in large and destructive avalanches.
Snowpack Summary
Surface snow is moist or wet on solar aspects and at low elevations. At upper elevations, previous strong wind has redistributed surface snow and scoured exposed areas.
50 to 60 cm of snow sits over a weak layer of facets, surface hoar and sun crust buried in mid February. Numerous large natural and remote-triggered avalanches have been failing on this layer throughout the region this week.
Another weak facet/crust/surface hoar layer, from late January, is buried 40 to 80 cm deep. This layer has been the culprit for many very large natural, remote and human-triggered avalanches near Whistler in recent days.
Weather Summary
Friday night
Partly cloudy. 10 to 20 km/h southwest ridgetop wind. Treeline temperature +2°C. Freezing level 2700 m.
Saturday
Mix of sun and cloud. 10 to 30 km/h southwest ridgetop wind. Treeline temperature +4°C. Freezing level 2300 m.
Sunday
Mostly cloudy with 1-5 cm of snow. 10 to 20 km/h northwest ridgetop wind. Treeline temperature -1°C. Freezing level 1700 m.
Monday
Sunny. 10 to 20 km/h north ridgetop wind. Treeline temperature -2°C. Freezing level 1600 m.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Remote triggering is a big concern, be aware of the potential for wide propagations and large, destructive avalanches at all elevations.
- Avoid thin areas like rocky outcrops where you're most likely to trigger avalanches on deep weak layers.
- A moist or wet snow surface, pinwheeling, and natural avalanches are all indicators of a weakening snowpack.
- Make conservative terrain choices and avoid overhead hazard.
Avalanche Problems
Persistent Slabs
Persistent weak layers have become active with recent snow loads and warm temperatures. Small avalanches have potential to step down to these layers. This problem is most likely triggered in wind-loaded areas at high elevations.
Aspects: North, North East, East, West, North West.
Elevations: Alpine, Treeline.
Likelihood: Likely
Expected Size: 1 - 2.5
Wind Slabs
Wind slabs may remain sensitive to rider triggers. Small wind slab releases may step down to weak layers in the upper snowpack to produce larger, more destructive avalanches.
Aspects: North, North East, East, South East, North West.
Elevations: Alpine, Treeline.
Likelihood: Possible - Likely
Expected Size: 1 - 1.5
Loose Wet
Warm temperatures and sunshine will destabilize the surface snow on sun-exposed slopes. Loose snow avalanches can trigger buried weak layers, producing large, destructive slab avalanches.
Aspects: South, South West, West.
Elevations: All elevations.
Likelihood: Likely
Expected Size: 1 - 1.5