Avalanche Forecast

Issued: Dec 14th, 2018 3:00PM

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

Alberta Parks matt.mueller, Alberta Parks

Tricky times out there. The alpine is not the place to be for the next while. Treeline is also a complex place at the moment. Travel cautiously, don't blindly trust the snowpack and avoid overhead exposure.

Summary

Confidence

High -

Weather Forecast

A South West flow will bring another pulse of snow overnight tonight. Expect about 5cm. Alpine winds will be around 80km/hr from the SW. As the storm plays through, the winds are expected to drop slightly. Alpine temperatures will also drop to -10 during the day.

Avalanche Summary

Lots of windslabs pulled our during the storm. Many were already blown in. Most were in the alpine and on easterly aspects and averaged sz2. There was also a report a skier remote sz2, 120cm deep and ran quite far. Specifics are unknown. We are definitely in the human triggered portion of this avalanche cycle.

Snowpack Summary

The recent storm snow has been widely redistributed by the strong SW winds. In sheltered areas at treeline, there is up to 40cm and the alpine varies from 40-100cm depending on wind exposure. Needless to say, the alpine is completely covered in new windslabs. Treeline is a bit more forgiving in terms of windslab distribution, windslabs aren't as widespread. The Dec 10th surface hoar/facet layer is down 20-30 at treeline. As far as surface hoar is concerned, we did find it, but it was actually hard to track down. Sheltered areas at treeline seem the most likely, but there could be pockets in more open terrain. Facets on the other hand, are very easy to find- nothing new there! We'll nail this layer's character down better as more observations are made. The deeper crusts, are mostly facetted out, but seem to be reasonably well glued together in low angle terrain.

Problems

Wind Slabs

An icon showing Wind Slabs
Lots of new snow and strong winds lately. Avoid exposing yourself to any wind prone areas. Watch for buried windslabs as the next storm rolls through.
Avoid freshly wind loaded features.If triggered the storm/wind slabs may step down to deeper layers resulting in large avalanches.Use conservative route selection, choose moderate angled and supported terrain with low consequence.

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

Elevations: Alpine, Treeline.

Likelihood

Very Likely

Expected Size

1.5 - 2.5

Deep Persistent Slabs

An icon showing Deep Persistent Slabs
There are a number of weak facet layers lurking deep in the snowpack. Be sure to dig and assess before jumping into ski terrain. Even pieces of small terrain could kick out a decent size avalanche.
Minimize overhead exposure during periods of heavy loading from new snow, wind.Avoid unsupported slopes.Dig down to find and test weak layers before committing to a line.

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 3

Valid until: Dec 15th, 2018 2:00PM