Avalanche Forecast

Archived

Dec 19th, 2024–Dec 20th, 2024

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Natural avalanches unlikely.

Alpine

Natural avalanches possible, human triggered probable.

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

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

Recent windslabs and warm temperatures are in a push/pull phase now. Warmth promotes settlement & improvement, yet it may also make things touchier if it gets too warm. Pay attention to aspect/solar input and air temperature if you're in avalanche terrain.

Confidence

Moderate

Avalanche Summary

No new avalanches have been reported.

Snowpack Summary

Warm temperatures and windslabs are the headliners today. Valley bottom had above zero degree temps, while treeline snuck in at -2. This has/will help stabilize windslabs, but expect them to still linger on all east aspects. If temperatures rise, or if the sun comes out, these slabs will become touchier. No change to the weak base layers. Snow depths are holding steady at about 80cm at treeline.

Weather Summary

Temperatures will fall tomorrow morning and settle at -8 by 8am. Daytime high will be -3 near the divide, likely above zero valley bottom. Winds will continue to be light out of the SW. Snow? Maybe a touch in the evening as a front moves through. Not enough accumulation to change anything for the better or worse.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

If triggered, wind slabs avalanches may step down to deeper layers resulting in larger avalanches.
Approach lee and cross-loaded slopes with caution.

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.

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.