Avalanche Forecast
Issued: Apr 10th, 2021 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs, Loose Wet and Cornices.
cgarritty,
Avalanche Canada
Stay tuned in to hazards lingering from the storm as you keep up the winter stoke. Wind slabs perched in steep leeward pockets, looming cornices, and fresh snow seeing its first sun exposure will all need to be managed on Sunday.
Summary
Confidence
Weather Forecast
Saturday night: Clearing. Moderate northwest winds easing to light by morning.
Sunday: Sunny. Light north winds. Alpine high temperature near -2 with freezing levels to 1300 metres, continuing to rise overnight.
Monday: Sunny. Light to moderate northeast winds. Alpine high temperatures around +1 with freezing levels to 1700 metres, remaining elevated overnight.
Tuesday: Sunny. Light to moderate northeast winds. Alpine high temperatures around +3 with freezing levels to 2000 metres.
Avalanche Summary
Early observations from Friday's storm showed touchy new storm slabs set up by the end of the day. This MIN report gives a good idea of the situation. Snowfall continued through the overnight period and although the bond of the new snow may have improved slightly by Saturday, the added load and the addition of solar exposure likely kept conditions quite reactive during the day.
Looking forward to Sunday, solar aspects may continue to shed loose snow with daytime warming and more wind loaded features will likely remain reactive to human triggering as well, even if a bit more stubborn.
Snowpack Summary
30-40 cm of new snow, tapering with elevation, accumulated through Friday night with moderate to strong southwest winds. This new snow is likely to establish a good bond with the old surface by Sunday, however steep wind loaded areas should remain suspect a bit longer.
The new snow and 10-15 more cm of older storm snow from last weekend sits on another crust on sun-exposed aspects, and on all aspects below about 1400 m. This older interface consists of a mix of dry wind affected or soft snow (depending on aspect) above 1400 m. This older snow layer did not seem to be getting involved in Friday's avalanche activity.
Cornices are large and looming along ridgelines and formed fragile new growth during Friday's storm. Their release is unpredictable, requiring a large berth if you're travelling above or below them.
Terrain and Travel
- Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
- Loose avalanches may start small but they can grow and push you into dangerous terrain.
- Pay attention to cornices and give them a wide berth when traveling on or below ridges.
Problems
Wind Slabs
Slab problems are likely to be restricted to wind loaded features by Sunday, but pinning down slab distribution may be tricky with winds that shifted north after the storm. Analyze slopes for wind loading patterns and test small, low-consequence features before stepping out.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Loose Wet
Surface snow will lose cohesion and become unstable with solar warming during the day. Avoid exposing yourself to terrain where a small wet loose release could have big consequences.
Aspects: South East, South, South West, West.
Elevations: All elevations.
Likelihood
Expected Size
Cornices
Cornices are large and looming along many ridgelines and will have formed fragile new growth with the recent snow and wind.
Aspects: North, North East, East, West, North West.
Elevations: Alpine.
Likelihood
Expected Size
Valid until: Apr 11th, 2021 4:00PM
