Avalanche Forecast

Issued: Dec 12th, 2019 4:00PM

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

Parks Canada Adam Greenberg, Parks Canada

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This is a great time to make conservative decisions as we are getting acquainted with early season persistent weak layers. The Akamina Parkway is closed for construction until December 21.

Summary

Weather Forecast

Friday: Cloudy with scattered flurries, up to 5cm of snow. Moderate NW to W winds, alpine high -7.

Saturday: Cloudy with sunny periods and isolated flurries. Light west winds, Alpine high -12.

Sunday: Cloudy with sunny periods and light to moderate westerly winds. Alpine high -12.

Snowpack Summary

15-25cm previous storm snow coupled with strong to extreme west winds has formed new slabs in the alpine and treeline. A melt freeze crust facet combo formed at the start of the season sits at the bottom of the snowpack. Though unlikely to be triggered by people, it is not impossible and we have seen other avalanches stepping down to this layer.

Avalanche Summary

No recent avalanche activity has been seen in the park, but recently we have seen windslabs stepping down to early season weak layers on east aspects in the alpine, and surrounding ski areas have been getting results to size 2 with explosives.

Confidence

Due to the number of field observations

Problems

Wind Slabs

An icon showing Wind Slabs

Strong to extreme winds have stripped fetches in the alpine, and new wind slabs exist at treeline and above. These will begin to settle as the weekend progresses.

  • Be careful with wind loaded pockets. Be aware of wide variation in snowpack depth
  • Be cautious as you transition into wind affected terrain.

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Persistent Slabs

An icon showing Persistent Slabs

Melt freeze crusts and facets from early season snowfalls are lurking at the bottom of the snowpack. Windslabs have been stepping down to this layer, and it may be possible for a person to trigger an avalanche in the right (wrong?) spot.

  • Avoid thin rocky or unsupported terrain features.
  • If triggered the wind slabs may step down to deeper layers resulting in large avalanches.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

2 - 3

Valid until: Dec 15th, 2019 4:00PM