Avalanche Forecast
Regions: Bow Valley, Highwood Pass, Kananaskis, North 40, Spray - KLakes.
The snowpack is very sensitive to human-triggering. Forecasters were able to easily remote and skier trigger avalanches failing down 40-50cm at treeline on Friday. Avoid steep, convex and unsupported slopes as the snowpack adjust to this new load.
Confidence
High
Avalanche Summary
On Friday numerous skier controlled size 1 avalanches were triggered by forecasters. These failures occurred down 40cm on the Nov 25 facet layer.
Snowpack Summary
A few cm's of new snow in the past 24hrs. The winds have been strong in the Alpine with many windward slopes stripped bare to rock, with pockets of hard wind slab on the lee side. There are two main layers of concern found in the snowpack. The Nov 25 facet layer is down 15 to 30cm and the Nov 16 surface hoar is buried 30 to 50cm. Both of these layers are producing whoomphs, cracking and very easy test score in snowpack tests. In addition, the basal layers are fully facetted. Forecasters have very little confidence in the snowpack.
Weather Summary
Sunday should be a mix of sun and cloud with temperatures climbing to -8C by midday. A couple of cm's of snow are expected, with generally light SW winds.
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.
- Remote triggering is a concern, watch out for adjacent and overhead slopes.
- Watch for areas of hard wind slab on alpine features.
Avalanche Problems
Persistent Slabs
Where the surface snow is dense enough to form a slab, the Nov 25 and 16 layer are reactive to skier traffic. Remote triggering is possible.
Aspects: All aspects.
Elevations: All elevations.
Likelihood: Very Likely
Expected Size: 1 - 2.5
Wind Slabs
Wind slabs are found along ridgelines and in gullied terrain. These avalanches will likely step down to the weak base layers.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood: Possible - Likely
Expected Size: 1 - 2