Avalanche Forecast

Issued: Jan 9th, 2024 3:30PM

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

Avalanche Canada Dvonk, Avalanche Canada

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Lots of wind in the past 24 hours (including reverse wind loading) has formed wind slabs in all alpine and open treeline locations. Cracking and remote triggering windslabs is evident of the changing snowpack.

Summary

Confidence

High

Avalanche Summary

A field team went in to the Dogleg area today. Extensive snow transport was happening all day. No new naturals were noted, but a skier remote wind slab to size 1 was triggered from 5 meters away in a gully feature on a SSE aspect ( evidence of reverse loading)

Snowpack Summary

Recent snow accumulations of up to 20cm is being re-distributed by strong and variable winds at ridgetop. Expect wind slabs averaging 30cm thick on virtually all aspects in Alpine terrain, and these do extend down into Treeline elevations in some areas. The reactivity of these wind slabs depends on the previous surface they have formed on. In areas where a buried crust exists, or a layer of weak facets, these new wind slabs will be more touchy. At Treeline and below the early December rain crust remains supportive for the most part. Unfortunately the incoming cold snap may start to change that. Otherwise the basal facets and depth hoar remain unchanged.

Weather Summary

Tuesday evening will bring an additional 5cm. This will total about 20cm of storm snow over the week. Tuesday saw winds in the 60-80km range from the NW at ridge tops.

Wednesday will see day time highs of -15 and cloudy skies. Wednesday evening the Arctic front moves in and current forecasts are showing temps in the -40 range, with out windchill. Yikes!

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Recent wind has varied in direction so watch for wind slabs on all aspects.
  • Be carefull around freshly wind loaded features.
  • Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
  • In areas where deep persistent slabs may exist, avoid shallow or variable depth snowpacks and unsupported terrain features.

Problems

Wind Slabs

An icon showing Wind Slabs

Cracking and a remote triggering an avalanche from 5 meters away today show the potential of these wind slabs.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Very Likely

Expected Size

1 - 2

Deep Persistent Slabs

An icon showing Deep Persistent Slabs

This problem will be with us all season. At higher elevations there is more concern that these deep persistent weak layers could be human triggerable.

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

Elevations: Alpine.

Likelihood

Unlikely - Possible

Expected Size

1.5 - 3

Valid until: Jan 10th, 2024 4:00PM