Avalanche Forecast
Regions: Brazeau, Churchill, Cirrus-Wilson, Fryatt, Icefields, Jasper, Maligne, Marmot, Miette Lake, Pyramid.
The new snow has made for good riding conditions in sheltered terrain. Limit exposure to overhead hazard as the new snow settles in - new wind slab and dry loose activity will likely step down into the basal weakness resulting in large avalanches.
Confidence
Moderate
Avalanche Summary
Patrol 93N noted a few natural avalanches - one deep persistent slab avalanche size 2.5 PR slopes, one loose dry starting in the alpine stepping to the basal weakness size 2.5 across from Mnt Coleman, and isolated dry loose avalanches up to size 1.5 on steep features in the Parker Ridge area.
Don't forget to post avalanche observations to the MIN.
Snowpack Summary
15-20cm new snow fell on Monday in the Icefields area; up to 10cm in the Maligne area. This new snow covers a sun crust on low elevation steep southerly slopes, old wind slab in expose areas, and surface facets in sheltered terrain. Moderate southwest winds are forming new wind slab immediate lees. The mid-pack is 20 to 40cm of low density facetted snow. The lower snowpack is generally weak with large facets and depth hoar at the base. Snowpack depth varies from 60 to 170cm.
Weather Summary
Residual cloud and with isolated flurries possible on Wednesday. Winds will be westerly and light with the freezing level at valley bottom. A building surface ridge of high pressure will bring a clearing trend Thursday into the weekend - daytime freezing level rising to 1500m on Friday.
Detailed weather forecasts from Avalanche Canada: https://avalanche.ca/weather/forecast
Terrain and Travel Advice
- If triggered, wind slabs avalanches may step down to deeper layers resulting in larger avalanches.
- Avoid shallow, rocky areas where the snowpack transitions from thick to thin.
Avalanche Problems
Wind Slabs
The new storm snow accompanied by moderate southwest wind is creating new wind slab near ridge crest and on isolated features at tree line.
Aspects: North, North East, East, South East, North West.
Elevations: Alpine, Treeline.
Likelihood: Likely
Expected Size: 1 - 2
Deep Persistent Slabs
The bottom of the snow pack is inherently weak with well developed Facets and Depth Hoar. Monday's 20cm of new snow will test this problem. Use caution is thin snowpack areas where human traffic may be able to trigger this layer.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood: Possible - Likely
Expected Size: 1.5 - 3.5
Loose Dry
This problem has shown the ability to scrub into the deep persistent layer. Solar aspects will likely see an increase in activity with the forecasted clearing trend.
Aspects: All aspects.
Elevations: All elevations.
Likelihood: Likely - Very Likely
Expected Size: 1 - 1.5