Avalanche Forecast

Issued: Jan 25th, 2021 4:00PM

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

Avalanche Canada dsaly, Avalanche Canada

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Remain cautious of wind slabs in steep and immediate lee features. Be wary of large cornices. 

Summary

Confidence

High - Confidence is due to a stable weather pattern with little change expected.

Weather Forecast

Monday night: Cloudy, isolated flurries / south winds, 15-25 km/h / alpine low temperature -12  

Tuesday: Cloudy, with sunny breaks / southeast winds, 20-30 km/h / alpine high temperature -10

Wednesday: Cloudy, isolated flurries / southeast winds, 20-30 km/h / alpine high temperature -12

Thursday: Cloudy, isolated flurries / south winds, 10 km/h / alpine high temperature -12 

Avalanche Summary

There have been no recent avalanche reports in the region. We're continuing to track a layer of surface hoar from early January which has been trending towards unreactive. The most recent activity reported on this layer comes from January 16, when professional operators reported a small (size 1) avalanche releasing 40 cm deep on the Jan 11th surface hoar layer. Observers south of Valemount also reported reactivity on the surface hoar buried down 45 cm. They saw shooting cracks and slab activity at 1700m on an easterly aspect. 

Snowpack Summary

A dusting of low density snow overlies a widespread layer of surface hoar. The snowpack boasts a variety of surfaces including scoured and pressed surfaces in exposed terrain, large cornices, isolated wind slabs, and variable wind affected and facetted snow in more sheltered terrain. Cold temperatures are encouraging surface faceting and breaking down wind slabs. A thin sun crust may be found on steep solar aspects. Below 1600 m, 20-30 cm of snow is settling above a decomposing melt freeze crust. 

A weak of layer of surface hoar can be found buried 35-60 cm deep. This layer last demonstrated reactivity over a week ago (Jan 16) in the south of the region near Valemount. It is most suspect in sheltered, open slopes at and below treeline. Although results from recent snowpack tests show increasingly resistant results (check out this MIN from near Barkerville), slope-specific assessment is warranted. 

Deeper in the snowpack, a couple of older persistent weak layers may still be identifiable from late and early December, consisting of surface hoar and a crust with faceted snow and buried anywhere from 70-150 cm deep. Prolonged periods of inactivity and unreactive snowpack test results suggest that these layers have trended towards dormancy. 

Terrain and Travel

  • Carefully evaluate steep lines for wind slabs.
  • Large cornice falls are dangerous on their own.
  • Approach steep open slopes at and below treeline cautiously, buried surface hoar may exist.

Problems

Persistent Slabs

An icon showing Persistent Slabs

A weak layer of surface hoar buried Jan 11 may be found 35-60 cm deep on open, sheltered slopes near and below treeline. Although likely unreactive to skiers, there is uncertainty in the distribution and sensitivity of this persistent slab problem across the region.

Aspects: All aspects.

Elevations: Treeline, Below Treeline.

Likelihood

Unlikely

Expected Size

2 - 3

Valid until: Jan 26th, 2021 4:00PM