Avalanche Forecast

Issued: Dec 8th, 2017 3:55PM

The alpine rating is moderate, the treeline rating is moderate, and the below treeline rating is low. Known problems include Wind Slabs, Deep Persistent Slabs and Loose Wet.

Avalanche Canada cgarritty, Avalanche Canada

Weaknesses deep in the snowpack will heal much more slowly than wind slabs. Keep your guard up around big overhead terrain and in thin snowpack areas in the alpine.

Summary

Confidence

Moderate -

Weather Forecast

Saturday: Mainly sunny with valley cloud due to lingering temperature inversion. Light west winds. Freezing level to 3500 metres with alpine temperatures around +4. Cooler at lover elevationsSunday: Mainly cloudy. Light west winds. Freezing level to 3500 metres with alpine temperatures around +6. Cooler at lower elevations.Monday: Mainly sunny with some valley cloud due to lingering inversion. Light southwest winds. Freezing level to 3500 metres with alpine temperatures around +7. Cooler at lower elevations.

Avalanche Summary

No new avalanches have been reported from this region. Although warm daytime temperatures and overnight cooling are likely helping bond recent wind slabs to the surface, the potential for releases deeper in the snowpack will remain elevated as these warm temperatures persist. Thin and variable snowpack depth areas will be the most likely trigger points for a deep release.Please submit your observations to the Mountain Information Network.

Snowpack Summary

Average snowpack depths at upper elevations in the region range from about 50-100 cm. Solar and temperature crusts are expected to have formed on the surface at higher elevations over the past two days. Below the surface, recent shifting winds extended wind slab formation to a wide range of aspects at treeline and above. The two crusts that were buried near the end of November can now be found approximately 30 cm and 60 cm down. A third crust from the end of October exists as a "facet/crust" combo near the base of the snowpack. Snowpack testing in the adjacent Kananaskis Country forecast region has yielded hard but sudden results on this layer.

Problems

Wind Slabs

An icon showing Wind Slabs
A recent wind shift from southwest to north means that wind slabs now exist on a wide range of aspects at higher elevations. Be especially cautious of reverse loaded or cross-loaded slopes that see sun exposure.
If triggered, wind slabs may step down to deeper layers and result in large avalanches.Use ridges or ribs to avoid pockets of wind loaded snow.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Deep Persistent Slabs

An icon showing Deep Persistent Slabs
Several persistent weak layers exist at the base of the snowpack. The risk of triggering one of these weaknesses will be elevated while warm weather persists at higher elevations.
Minimize your exposure to overhead avalanche terrain.Be aware of triggering thin areas that may propagate to deep instabilites more easily.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

2 - 3

Loose Wet

An icon showing Loose Wet
Warm, sun-exposed slopes could continue to produce wet loose avalanches either naturally or with rider triggers on Saturday, especially in steeper terrain. This problem may expand to northerly aspects as warming persists.
Minimize exposure to steep, sun exposed slopes when the solar radiation is strong.Be cautious of sluffing in steep terrain, particularly where the debris flows into terrain traps.

Aspects: North, North East, East, South East.

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Dec 9th, 2017 2:00PM