Avalanche Forecast

Archived

Jan 22nd, 2024–Jan 23rd, 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.

Previous storm snow and warming temps this week will consolidate and change the condition of the surface slab. Dig down and test the reactivity of the new snowpack before you commit to a line or feature.

Confidence

Moderate

Avalanche Summary

The field Team was in the Icefields on Monday. Tests showed easy results with the potential to propagate in connected features at the storm interface. Recent natural activity in the region has been associated with this persistent weak layer.

Snowpack Summary

As a general observation, the snowpack continues to be weak and largely unsupportive, though recent storm snow has improved travel. HS at tree-line is 45-75cm. Ski penetration is down 20-30cm which shows that while shallow, there is some structure in the mid-pack. A faceted interface down ~25cm shows up in snowpack tests; while in the field, reactivity will be subject to the strength of the slab over that layer.

Weather Summary

Icefields Overnight: Clear periods. Alpine Low -6 °C. Light winds.

Tuesday: Cloudy with sunny periods and a trace of flurries Alpine high, -5 °C. Light winds. Fzl up to 1500m.

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

Terrain and Travel Advice

Be carefull around freshly wind loaded features.
Back off if you encounter whumpfing, hollow sounds, or shooting cracks.

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.