Avalanche Forecast
Regions: Brazeau, Churchill, Cirrus-Wilson, Fryatt, Icefields, Jasper, Maligne, Marmot, Miette Lake, Pyramid.
The snowpack is still recovering from a warming event this week. Surface instabilities remain likely to trigger, and have a high potential to step down resulting in large, dangerous avalanches.
Make conservative terrain decisions, and avoid overhead hazard.
Confidence
Moderate
Avalanche Summary
Road patrols on the icefields Parkway Wednesday observed a widespread wet loose cycle to size 2 in steep terrain on all aspects, triggering persistent and deep persistent slab avalanches in some areas to size 3. Storm slab avalanches were also observed occurring on solar aspects.
New wet loose and slab avalanches continue to be observed, especially at tree line, along the Icefields Parkway through Thursday. Poor visibility into terrain above 2000m.
Snowpack Summary
10-20 cm of new snow is settling quickly. Warm temperatures on Wednesday have resulted in moist surface snow to 2600m. At 2200m the top 80cm remains moist despite cooling temperatures. At treeline and below, the 70-90 cm from earlier in March has settled into a supportive midpack. This bridges a complicated and reactive deep persistent weakness. Where the snowpack is shallow, the bridging is not strong and triggering a large avalanche is very possible.
Weather Summary
Friday
Cloudy with scattered flurries. Accumulation: 4 cm. Alpine temperature: High -2 °C. Ridge wind light to 20 km/h. Freezing level: 2000 metres.
Terrain and Travel Advice
- Make conservative terrain choices and avoid overhead hazard.
- Remote triggering is a concern; avoid terrain where triggering overhead slopes is possible.
Avalanche Problems
Persistent Slabs
This avalanche problem is associated with a weak facet and crust layer buried at the end of January approximately 80cm down in sheltered areas. This includes a crust layer formed in early March below the recent storm snow which is prominent on solar aspects.
Aspects: All aspects.
Elevations: All elevations.
Likelihood: Likely
Expected Size: 2 - 3.5
Loose Wet
If triggered, it is possible to initiate lower weaker persistent layers creating a large avalanche.
Aspects: All aspects.
Elevations: Treeline, Below Treeline.
Likelihood: Likely - Very Likely
Expected Size: 1 - 2.5
Deep Persistent Slabs
Avalanches in the upper snowpack are likely to step down to this deeper weak layer.
Aspects: All aspects.
Elevations: All elevations.
Likelihood: Possible
Expected Size: 2 - 4