Avalanche Forecast

Issued: Dec 26th, 2019 4:13PM

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

Parks Canada snow safety, Parks Canada

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Though natural avalanche activity has tapered off, human triggering remains likely. Choose less committing terrain and avoid large overhead hazard.

There have been a few close calls already this week.

Summary

Weather Forecast

Friday will see mainly cloudy skies with brief periods of sun and isolated flurries. Alpine high of -16 with a possible temperature inversion. Moderate winds from the West. No significant snow accumulations in the forecast.

Snowpack Summary

Surface hoar growth up to 5mm observed below tree line. Moderate SW winds are redistributing the 30-60cm of recent storm snow and forming wind slab on lee aspects. Below the new snow the snowpack structure is generally weak, consisting of facets and depth hoar and a Nov crust up to 2500m.

Avalanche Summary

No new natural avalanche activity in the past two days. Explosive avalanche control yesterday at Sunshine ski area produced a sz 2 deep persistent slab. Recent reports of skier triggered avalanches within the region.

Confidence

Due to the number of field observations on Thursday

Problems

Wind Slabs

An icon showing Wind Slabs

With 30-60cm of storm snow available for transport accompanied by the moderate to strong SW winds, expect fresh wind slab formation in the alpine and exposed areas at tree line.

  • If triggered the wind slabs may step down to deeper layers resulting in large avalanches.
  • Use caution in lee areas. Recent wind loading have created wind slabs.

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

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 2

Deep Persistent Slabs

An icon showing Deep Persistent Slabs

The weak, faceted lower snowpack remains stressed by the new storm snow at all elevations. If triggered the deep facets it will result in a very large avalanche.

  • Be aware of the potential for full depth avalanches due to deeply buried weak layers.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

2 - 3.5

Valid until: Dec 27th, 2019 4:00PM