Avalanche Forecast

Archived

Feb 2nd, 2024–Feb 3rd, 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.

Below Treeline

Natural avalanches unlikely.

Alpine

Natural avalanches unlikely, human triggered possible.

Treeline

Natural avalanches unlikely.

Below Treeline

Natural avalanches unlikely.

Regions

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

Cool overnight temperatures on Friday will create a hard crust up to 2500m. This cooling trend will lower the hazard rating and make travel easier but the ski quality will remain poor.

Confidence

Moderate

Avalanche Summary

Natural avalanche activity tapered off with no new avalanche activity observed on the Icefields Parkway or Maligne Lake road today.

Previous widespread avalanche activity over the past week produced numerous natural avalanches at all elevations. This included some impressive avalanches up to size 3.5 at higher elevations, as well as loose wet up to size 2.

Snowpack Summary

Previous high freezing levels, rain, and solar radiation has formed a surface crust up to 2500m. Cooling temperatures will solidify this crust but at least it will become supportive to ski traffic.

Previous Strong S and SW winds have scoured the alpine leaving behind isolated pockets of wind slab in leeward terrain

Persistent weak layers formed in early January are down 20-30cm in sheltered areas. Well developed facets and depth hoar make up the bottom of the snowpack.

Weather Summary

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

Saturday Mainly cloudy with isolated flurries. Trace precipitation. Alpine High -4 °C. Light ridge wind. Freezing level 1900m

Sunday Scattered flurries. Accumulation 2-4 cm. Ridge wind 15 km/h. Freezing level 1600

Monday Cloudy with sunny periods. Light ridge wind. Freezing level valley bottom

Terrain and Travel Advice

Make conservative terrain choices and avoid overhead hazard.
Stick to non-avalanche terrain or small features with limited consequence.

Problems

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.

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.