Avalanche Forecast

Archived

Feb 7th, 2024–Feb 8th, 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 at lower elevations are generally poor due to a very shallow snowpack. Conditions improve above 2100m where the crust is supportive to skiers. Some acceptable skiing is found at higher elevations, but it is challenging to get to and from that zone!

Confidence

High

Avalanche Summary

Nothing new today.

Snowpack Summary

Some moist surface snow was observed this afternoon at lower elevations. The recent storm snow is settling and now averages 5 to 15cm over the Feb 3 crust. This crust is supportive to skiers above 2100m 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. Very isolated wind slab development has been observed in the alpine in wind prone areas.

Weather Summary

Thursday should bring a mix of sun and cloud with a slight chance of flurries. Snowfall accumulations will only amount to 2-3cm with light westerly winds and temperatures near -5C.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

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

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.