Avalanche Forecast
Issued: Feb 16th, 2020 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs and Deep Persistent Slabs.
deryl kelly,
Parks Canada
Stale weather to remain through Monday. Forecasts then show a slow increase in temperatures and, sunny skies.
The late winter sun is starting to penetrate the snowpack. Expect some localized instability on steep, solar aspects in the afternoon.
Summary
Weather Forecast
Zonal flow from west to east cycling through the region. A shallow trough holding the last of the moisture moving through, before flow shifts from the Northwest with the approaching ridge on the pacific. Clearing and slight warming by Tuesday/Wednesday.
Find the Alberta Rockies weather synopsis here: Avalanche Canada Mountain Weather Forecast
Snowpack Summary
Variable strength windslab on the surface. Pronounced cornice development on northerly aspects and cross loaded features treeline and above. A supportive mid-pack is bridging the deeper basal facets and depth hoar in some locations.
Average HS at treeline: ~180cm.
Avalanche Summary
Previous public MIN (Mountain Information Network) report of natural size 2, southwest aspect at treeline in the Maligne Valley (thanks @Kaylaolde!!). Field team in Whistler/Portal Creek observed no recent natural avalanche activity; ski-pen 10-15cm.
This area is now open after a seasonal delayed access restriction to protect the Woodland Caribou.
Confidence
Intensity of incoming weather systems is uncertain on Tuesday
Problems
Wind Slabs
Wind slabs are very prevalent with previous loading in lee features. Sensitivity will vary with local loading and wind patterns.
- Watch for pockets of hard windslab in steep alpine terrain features..
- Assess start zones carefully and use safe travel techniques.
Aspects: North, North East, East, South East, North West.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Deep Persistent Slabs
Shallow snowpack areas and/or large triggers such as cornice failures could trigger this deep layer. The consequences would be severe!
- If triggered the wind slabs may step down to deeper layers resulting in large avalanches.
Aspects: All aspects.
Elevations: Treeline, Below Treeline.
Likelihood
Expected Size
Valid until: Feb 17th, 2020 4:00PM
