Avalanche Forecast

Issued: Dec 5th, 2017 3:00PM

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

Alberta Parks michael.olsthoorn, Alberta Parks

Another day of good skiing.  Wind effect has started to show up near ridge line.  Careful evaluation is recommended here and for cross loaded feature.

Summary

Confidence

High -

Weather Forecast

The forecast for Wednesday will bring an Alpine temperature of 1c and a freezing level of 1800m.  Winds will continue from the northwest 25-35km/h.  Thursday and Friday will bring sunny skies with the freezing levels rising to 2800m along with NW winds around 30km/h.

Avalanche Summary

A few loose dry avalanches up to size 2 mostly on E to SE aspects, most likely from the recent NW winds.

Snowpack Summary

The recent NW winds have started to create windslabs on lee features and extent down the slope. Some wind pressed snow was observed on the windward aspects. Evidence of moderate wind loading was observed on cross loaded features in the alpine. The November crust layers are buried between 50 and 70cm. The basal layers of the snowpack are made up of a mix of crusts from October along with facets. These layers continue to show moderate to hard results in snowpack stability tests. The upper snowpack will change and become denser when the warm weather rolls in creating a slab on top of the November raincrust.

Problems

Persistent Slabs

An icon showing Persistent Slabs
Remember, in shallow areas it is still possible to trigger the deeper layers and wake up the weak facets around the October crusts.
Be cautious in shallow snowpack areas where triggering is more likely.

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

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

2 - 3

Wind Slabs

An icon showing Wind Slabs
Recent NW winds have created slabs 30-50cm deep are being encountered in the Alpine on S and E aspects. Be cautious near ridgeline for wind loading, especially on lee features.
Avoid lee and cross-loaded terrain near ridge crests.Use caution in lee areas. Recent wind loading has created wind slabs.

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

Elevations: Alpine.

Likelihood

Possible - Likely

Expected Size

1 - 2

Valid until: Dec 6th, 2017 2:00PM