Avalanche Forecast

Archived

Jan 5th, 2024–Jan 7th, 2024

Alpine

Natural avalanches unlikely.

Treeline

Natural avalanches unlikely.

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

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

Up to 10cm of snow is forecast to fall in the region late in the day on Saturday. As the snow arrives we expect the danger to increase back into the Moderate range so keep a close eye on the weather as you travel.

Confidence

Moderate

Avalanche Summary

Nothing new observed in the last couple of days.

Snowpack Summary

4-6cm of recent snow at treeline and above has been moved around by light winds out of the SW. This snow has fallen on a variety of different snow surfaces from hard windslabs, rocks and some very isolated surface hoar at lower elevations. The December 5th rain crust can still be found down 30-40cm but it is breaking down in lower elevation areas. The main concern is the weak basal facets and depth hoar and concerns for triggering from thin steep snowpack areas.

Weather Summary

Temperatures on Saturday will be in the -8C range with overnight winds (Friday to Saturday) in the strong to moderate range out of the SW decreasing to light by Saturday morning. During the late afternoon on Saturday, expect winds to switch out of the NE as cooler temperatures arrive. This upslope flow is forecast to give us around 10cm of snow.

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.
Dial back your terrain choices if you are seeing more than 20 cm of new snow.

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.