Avalanche Forecast

Issued: Jan 5th, 2021 4:00PM

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

Avalanche Canada MBender, Avalanche Canada

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Heavy snowfall combined with strong to extreme wind overnight Tuesday will push avalanche danger to high at upper elevations. Give the new snow time to stabilize.

Summary

Confidence

Moderate - Uncertainty is due to the timing, track, & intensity of the incoming weather system.

Weather Forecast

Tuesday Night: Heavy snowfall or rain, accumulation 20-40 cm, strong to extreme southwest wind, treeline high temperature 0, freezing level 1100 m.

Wednesday: Mainly cloudy, strong wind easing to moderate southwest, treeline high temperature 0, freezing level 1200 m.

Thursday: Sun and cloud, lightto moderate southwest wind, treeline high temperature 2, freezing level rising to 1500 m.

Friday: Snow or rain, moderate southwest wind, freezing level 900 m.

Avalanche Summary

There are no recent avalanches to report, although I would expect an increase in storm and wind slab avalanche activity at upper elevations overnight Tuesday and very early morning Wednesday. As well, lower elevations may see an increase in wet loose activity in steep terrain below the 1100 m elevation band.

Snowpack Summary

Precipitation arriving Tuesday afternoon and evening was expected to arrive as snow at uppermost elevations. Recent storm totals for the last week at upper elevations are upwards of 200 cm. This snow has likely seen extensive wind effect but we have received no alpine observations. Recent snow may contain and/or sit on a crust. At lower elevations, the previously rain soaked mid to lower snowpack will be dense and refrozen, or still wet below 1000 m.

The remainder of the snowpack is well-settled.

Terrain and Travel

  • Dial back your terrain choices if you are seeing more than 30 cm of new snow.
  • Continue to make conservative terrain choices while the storm snow settles and stabilizes.
  • Be especially cautious as you transition into wind affected terrain.
  • Avoid lee and cross-loaded terrain.

Problems

Storm Slabs

An icon showing Storm Slabs

Heavy snowfall combined with wind will likely create widespread and reactive storm slabs at uppermost elevations. Forecast strong to extreme southwest wind Tuesday night has likely created deep deposits in exposed lee terrain.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Very Likely

Expected Size

1.5 - 2.5

Loose Wet

An icon showing Loose Wet

Rain on snow at lower elevations may create conditions for wet loose avalanches.

Aspects: All aspects.

Elevations: Treeline, Below Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2

Valid until: Jan 6th, 2021 4:00PM