Avalanche Forecast

Archived

Feb 5th, 2024–Feb 6th, 2024

Alpine

Natural avalanches unlikely, human triggered possible.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Natural avalanches unlikely.

Alpine

Natural avalanches unlikely, human triggered possible.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Natural avalanches unlikely.

Alpine

Natural avalanches unlikely, human triggered possible.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Natural avalanches unlikely.

Regions

Jasper, Brazeau, Churchill, Cirrus-Wilson, Fryatt, Icefields, Maligne, Marmot, Miette Lake, Pyramid.

Recent snowfall sits over a deteriorating, and now breakable, crust.

Continue to use caution on larger slopes in the alpine or at treeline as our persistent problems remain.... persistent.

Confidence

Moderate

Avalanche Summary

No new avalanche activity has been observed or reported on the Icefields Parkway or Maligne Lake Road since Friday.

A period of warm temperatures at the end of January caused a widespread avalanche cycle with numerous natural avalanches at all elevations up to size 3.5.

Snowpack Summary

6 cm of recent snow sits over a 1-3cm breakable crust. This crust becomes weaker as you gain elevation and will only support the weight of a skier or snowboarder on due south aspects.

Persistent weak layers formed in early January are down 20-30cm. This layer has been reactive in snowpit tests with moderate Extended Column results propagating across the entire column. Bottom of the snowpack is made up of well-developed facets & depth hoar creating our deep persistent problem

Weather Summary

The Mountain Weather Forecast is available at Avalanche Canada https://avalanche.ca/weather/forecast

Tuesday Cloudy with scattered flurries. Accumulation: 2-5 cm. High -3. Wind SW 10-25 km/h. Freezing level 1800m

Wednesday Sun/cloud & isolated flurries. No precipitation. Freezing level valley bottom.

Thursday Mainly cloudy with isolated flurries. Trace precipitation. West wind10-20 km/h.

Terrain and Travel Advice

Avoid shallow snowpack areas, rock outcroppings and steep convex terrain where triggering is most likely.
This avalanche problem is difficult to trigger but if so, consequences are serious.

Problems

Persistent Slabs

Persistent Slab avalanches are the release of a cohesive layer of snow (a slab) in the middle to upper snowpack, when the bond to an underlying persistent weak layer breaks. Persistent layers include: surface hoar, depth hoar, near-surface facets, or faceted snow. Persistent weak layers can continue to produce avalanches for days, weeks or even months, making them especially dangerous and tricky. As additional snow and wind events build a thicker slab on top of the persistent weak layer, this avalanche problem may develop into a Deep Persistent Slab.

Deep Persistent Slabs

Deep Persistent Slab avalanches are the release of a thick cohesive layer of hard snow (a slab), when the bond breaks between the slab and an underlying persistent weak layer deep in the snowpack. The most common persistent weak layers involved in deep, persistent slabs are depth hoar or facets surrounding a deeply buried crust. Deep Persistent Slabs are typically hard to trigger, are very destructive and dangerous due to the large mass of snow involved, and can persist for months once developed. They are often triggered from areas where the snow is shallow and weak, and are particularly difficult to forecast for and manage.