Avalanche Forecast

Archived

Dec 16th, 2022–Dec 17th, 2022

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 possible, human triggered probable.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Natural avalanches unlikely.

Regions

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

Any avalanche that initiates will likely involve the entire snowpack. Stick to conservative terrain and be patient as we wait for the snowpack to settle out this winter.

Confidence

High

Avalanche Summary

No new avalanches reported.

Snowpack Summary

Skiing in the Murray moraines area on Friday we found around 100-125cm of snow in treeline areas. In general, there is a weak layer at the midpack down 60-80cm. In some areas at treeline and below this is a surface hoar layer and in other areas its the main interface where the upper snowpack is overlying the basal facets. The take away is that regardless of the interface exactly, its failing in snowpack tests in the moderate range in very sudden collapses. Whumpfing is common these days which indicates that the layer if failing with a skiers weight.

As soon as there is the potential for a slab in the upper snowpack due to winds or settlement, stick to convervative terrain.

Its a different snowpack this year so be sure to evaluate your decisions before moving into a feature. When stability is the question, terrain is the answer.

Weather Summary

Temperatures area again falling this upcoming weekend with highs in the mid 20s. Winds will be light but over the next few days we may see up to 10cm of new snow. Expect this new snow to be cold smoke low density powder!

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

Be especially cautious as you transition into wind affected terrain.
Avoid convexities, steep unsupported terrain and rocky outcroppings.
Avoid shallow, rocky areas where the snowpack transitions from thick to thin.

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.

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.