Avalanche Forecast

Issued: Nov 28th, 2020 4:00PM

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

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Although fresh snow has stopped falling, the wind is continuing to redistribute it onto wind-protected slopes. With all that additional weight it might as well be snowing on those slopes. Danger ratings remain elevated. Go carefully avoiding steep and wind-loaded slopes.

Summary

Confidence

Moderate - Uncertainty is due to the speed, direction, or duration of the wind and its effect on the snowpack.

Weather Forecast

Pull up your hood or your toque will be blowin' away -- it's windy!

SATURDAY NIGHT: Dry. Treeline temperatures around -9C. Strong southwest winds.

SUNDAY: Windy, with strong southwesterly winds at ridgetop. Dry. Freezing level rising throughout the days to around 1400 m.

MONDAY: 5-15 cm new snow. Strong southwesterly winds continue. Freezing level around 1500m.

TUESDAY: Strong southwesterly winds continue. Dry. Cooler temperatures around -5 to -10 C

Avalanche Summary

As of mid-day Saturday reports from the field are sparse. I suspect there is evidence of natural avalanches from Friday's storm and Saturday's wind. Check the MIN for weekend reports from the field.

Snowpack Summary

Snow depths are approximately 150 cm in the north west of the region (Pine Pass), 180 cm in the south (Renshaw, Kakwa) and 100 cm in the the north east (Tumbler ridge).

In the deeper areas, successive storms have resulted in deep powder in the upper snowpack. The wind is changing that because it will certainly be blown into denser wind deposits. The question is whether windward slopes will become stripped of the recent snow.

Most likely the most significant instabilities are within or at the base of the most recent storm snow, approximately 50 cm below the snow surface.

Crusts have been reported towards the base of the snowpack. These are of most concern on steep terrain in thinner snowpack areas.

Terrain and Travel

  • Dial back your terrain choices if you are seeing more than 30 cm of new snow.
  • Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
  • Avoid exposure to overhead avalanche terrain during periods of heavy loading from new snow, wind or rain.

Problems

Storm Slabs

An icon showing Storm Slabs

30-70 cm of snow fell with the highest amounts in the south. Strong southwest winds are building deep windslabs at treeline and alpine elevations on lee and crossloaded slopes. Storm Slab problems will evolve into Wind Slab problems on north through east facing slopes.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Very Likely

Expected Size

1.5 - 2.5

Valid until: Nov 29th, 2020 4:00PM