Avalanche Forecast
Regions: Brazeau, Churchill, Cirrus-Wilson, Fryatt, Icefields, Jasper, Maligne, Marmot, Miette Lake, Pyramid.
Natural avalanche activity is still being observed and human triggering of avalanches remains likely. It also looks like the avalanche hazard may increase again on Tuesday with precipitation, wind, and rising temperatures in the forecast. It won't take much to overload our fragile snow pack.
Confidence
Moderate
Avalanche Summary
A field team observed 3 new size 2 natural avalanches in the icefields area on Saturday. They appeared to be a mix of the wind slab, persistent slab, and deep persistent slab problems, which occurred in steep rocky terrain in the alpine and at tree line.
They also noted very large whoomphs while traveling on skis, indicating the snowpack is still primed for triggering large avalanches.
Snowpack Summary
Wind slabs exist in lee features throughout tree line and alpine areas. The 70-90 cm from earlier in March has settled into a supportive slab. Below this, the snowpack is complicated and reactive, having multiple crusts and facet layers including the deep persistent basal layer.
Weather Summary
Monday
A mix of sun and cloud with isolated flurries.
Alpine temperature: High -4 °C.
Ridge wind west: 20 km/h gusting to 55 km/h.
Tuesday
Flurries.
Accumulation: 11 cm.
Alpine temperature: Low -6 °C, High 0 °C.
Ridge wind southwest: 15 km/h gusting to 45 km/h.
Wednesday
Mainly cloudy with isolated flurries.
Alpine temperature: Low -1 °C, High 0 °C.
Ridge wind south: 10-30 km/h.
Terrain and Travel Advice
- Make conservative terrain choices and avoid overhead hazard.
- Fresh snow rests on a problematic persistent slab, don't let good riding lure you into complacency.
- Remote triggering is a concern; avoid terrain where triggering overhead slopes is possible.
Avalanche Problems
Wind Slabs
If triggered, expect to initiate lower weaker persistent layers creating a large avalanche.
Aspects: North, North East, East, South East, North West.
Elevations: Alpine, Treeline.
Likelihood: Likely
Expected Size: 1 - 2
Persistent Slabs
This avalanche problem is associated with a weak facet and crust layer buried at the end of January approximately 70cm 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
Deep Persistent Slabs
Well developed facets and depth hoar at the bottom of the snow pack can produce large avalanches. Several big avalanches released during and immediately after the March 7th storm. Be suspicious of any slopes that have not released naturally.
Aspects: All aspects.
Elevations: All elevations.
Likelihood: Possible
Expected Size: 2.5 - 3.5