Avalanche Forecast

Archived

Feb 8th, 2024–Feb 9th, 2024

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.

Alpine

Natural avalanches unlikely.

Treeline

Natural avalanches unlikely.

Below Treeline

Natural avalanches unlikely.

Regions

Kananaskis, Bow Valley, Highwood Pass, North 40, Spray - KLakes.

Travel conditions vary at lower elevations. Generally there is 5-15cm overtop of a supportive crust creating OK skiing and travel.

Confidence

High

Avalanche Summary

Nothing new today.

Snowpack Summary

The recent storm snow is settling and now averages 5 to 15cm over the Feb 3 crust. A sun crust can be found on steeper solar aspects. This crust was mostly supportive in the valley bottom and extends at least as high as 2500m. The bond at the storm snow - crust interface is mainly good, except on steep northerly aspects in the alpine where some previous sluffing was observed. Very isolated wind slab development has been observed in the alpine in wind prone areas and on lee features.

Weather Summary

We should get 4cm of snow by the time we wake up Friday morning. The day will bring clouds and sunny periods with an alpine high temperature of -12c. Winds are to be 10km/hr from the NW.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

In areas where deep persistent slabs may exist, avoid shallow or variable depth snowpacks and unsupported terrain features.
Back off if you encounter whumpfing, hollow sounds, or shooting cracks.
Be carefull with sluffing in steep terrain, especially above cliffs and terrain traps.

Problems

Wind Slabs

Wind Slab avalanches are the release of a cohesive layer of snow (a slab) formed by the wind. Wind typically transports snow from the upwind sides of terrain features and deposits snow on the downwind side. Wind slabs are often smooth and rounded and sometimes sound hollow, and can range from soft to hard. Wind slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.

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.