Avalanche Forecast

Issued: Feb 5th, 2019 4:12PM

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

Avalanche Canada kdevine, Avalanche Canada

The unusual danger rating is due to a buried weak layer that exists mainly at treeline and below. It is easily triggered by humans and there is the potential for large avalanches at lower elevations. Choose low angled terrain, especially in the trees

Summary

Confidence

High -

Weather Forecast

TUESDAY NIGHT - Clear / northwest winds 10-15 km/h / alpine low temperature near -19WEDNESDAY - Mainly sunny / northwest winds 10-15 km/h / alpine high temperature near -13THURSDAY - Mainly cloudy with light flurries, 3-5 cm / southwest winds 10-15 km/h / alpine high temperature near -12FRIDAY - A mix of sun and cloud / northeast winds, 15-25 km/h / alpine high temperature near -16

Avalanche Summary

Natural avalanche activity began to slow down on Sunday, but a persistent weak layer that was buried in mid January continues to be reactive to human triggers. This layer is sensitive enough for humans to trigger avalanches remotely (from a distance). Human triggered avalanches up to size 2 were reported on both Sunday and Monday. This layer has been the most reactive at treeline and below.Widespread avalanche activity was reported on Saturday. Natural avalanches to size 3 and human triggered avalanches to size 2 were reported. Many of these failed on the mid January persistent weak layer. There is a great MIN report here detailing the reactivity of the mid January layer in Allen creek on Saturday.There were reports of a few human triggered avalanches to size 2 occurring at treeline and below on Friday. Some of these were remote triggered (triggered from a distance), and failed on the in mid January layer.There are two great MIN reports that outline how reactive the mid January layer was on Friday. They can be found here and here.

Snowpack Summary

30-60 cm of recent new snow is sitting on surface hoar (feathery crystals), facets (sugary snow) and a crust on sun-exposed slopes. In many areas, recent strong winds have redistributed the new snow and formed wind slabs on all aspects due to shifting wind directions.The most notable feature in the snowpack at this time is a persistent weak layer that was buried in mid January, which is now buried 50-80 cm. This layer consists of surface hoar and a crust on sun-exposed slopes. It is most prominent at treeline and below, and continues to produce avalanches.

Problems

Persistent Slabs

An icon showing Persistent Slabs
50-80 cm of snow sits above a weak layer of surface hoar and crust that was buried in mid January. This layer continues to be reactive to human triggering.
Any steep opening in the trees should be treated as suspect right now.Choose low angled terrain.

Aspects: All aspects.

Elevations: Treeline, Below Treeline.

Likelihood

Possible - Likely

Expected Size

1.5 - 3

Wind Slabs

An icon showing Wind Slabs
30-60 cm of recent snow has been redistributed by recent winds in many areas, forming wind slabs on all aspects due to a shift in wind direction.
If triggered, wind slabs may step down to deeper layers and result in even larger avalanches.Be careful with wind loaded pockets, especially near ridge crests and roll-overs.

Aspects: All aspects.

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Feb 6th, 2019 2:00PM