Avalanche Forecast

Issued: Jan 3rd, 2022 3:00PM

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

Avalanche Canada JSmith, Avalanche Canada

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Continued strong northeasterly winds are expected to form reactive wind slabs in open terrain at all elevations.

The best and safest riding will be on wind-sheltered slopes that have soft snow without any slab properties. 

Summary

Confidence

Moderate - Uncertainty is due to the limited number of field observations.

Weather Forecast

MONDAY NIGHT: Partly cloudy / Strong northeast wind / Low of -27

TUESDAY: Sunny / Strong northeast wind / High of -21

WEDNESDAY: Sunny / Moderate northwest wind / High of -23

THURSDAY: Cloudy with flurries; 5-15 cm / Strong southwest wind / High of -19

Avalanche Summary

Natural and explosive triggered storm slab avalanches up to size 3.5 were reported in the alpine on Sunday.

If you are out in the mountains, let us know what you see by filling out a Mountain Information Network report! ?

Snowpack Summary

Continued strong northeasterly winds are expected to form reactive wind slabs on lee features at all elevations.

Freshly formed wind slabs are most likely to be found on south and westerly aspects, but older wind slabs may be found on all aspects. Recently formed wind slabs may remain reactive to human triggers for longer than is typical due to the weak facets (sugary snow) they are sitting on.

Two layers of surface hoar exist within the upper snowpack in protected areas at treeline and below; one is down 40-60 cm (Dec 21) and the other is down 60-100 cm (Dec 18). The distribution of these layers appears to be relatively isolated, but information is limited and there has been very little feedback with recent benign weather pattens.

The early December rain crust is up to 10cm thick, down 80-150cm in the snowpack, and exists to an average of 1400m in elevation. Up to 2mm facets have been reported above this crust, and it is producing hard but sudden planar results in snowpack tests in areas north of Terrace. 

Terrain and Travel

  • Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
  • Be aware of highly variable recent wind loading patterns.
  • The best and safest riding will be on slopes that have soft snow without any slab properties.
  • Look for signs of instability: whumphing, hollow sounds, shooting cracks, and recent avalanches.
  • Keep your guard up at lower elevations. Wind slab formation has been extensive.

Problems

Wind Slabs

An icon showing Wind Slabs

Continued strong northeasterly winds are expected to form reactive wind slabs on lee features at all elevations.

Freshly formed wind slabs are most likely to be found on south and westerly aspects, but older wind slabs may be found on all aspects.

The freshly formed slabs may remain reactive for longer than is typical because they are sitting on weak facets (sugary snow).

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1.5 - 2.5

Valid until: Jan 4th, 2022 3:00PM