Avalanche Forecast

Issued: Jan 2nd, 2021 4:00PM

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

Avalanche Canada ahanna, Avalanche Canada

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New snow and wind will continue to build fresh and reactive storm slabs. Choose simple terrain and avoid overhead hazard.

Summary

Confidence

Moderate - Uncertainty is due to difficult to forecast freezing levels.

Weather Forecast

Saturday night: Wet snow, 15-20 cm, strong southwest wind easing to moderate northwest, freezing level dropping 1400 m to 800 m.

Sunday: Snow 15-25 cm, moderate to strong southwest wind, alpine high temperature -5, freezing level 800 to 1000 m.

Monday: Snow, 15-20 cm, light southwest wind, alpine high temperature -1, freezing level 1200 m.

Tuesday: Flurries, southwest wind increasing to strong, alpine high temperature -4, freezing level 1000 m.

Avalanche Summary

Slab avalanche activity is expected at upper elevations where the precipitation is falling as snow.  

Wet loose avalanches may occur at lower elevations where the snow has been soaked by rain.

Natural (size 1) and explosive triggered (size 2) were reported in the North Shore mountains on Thursday and Friday during the storm.

There were numerous avalanches up to size 1.5 reported in the North Shore mountains during the storm on Wednesday. It is likely that a widespread natural avalanche cycle occurred throughout the region on Wednesday as well, especially at higher elevations.

Snowpack Summary

30-50 mm of precipitation is forecast to fall Saturday night and over the day Sunday. The snow line may rise as precipitation eases slightly Saturday evening, before dropping down below 800 m as a cold front comes through overnight.

This will bring recent snow amounts at upper elevations to as much as 200-300 cm. The new snow sits on a crust in many areas, and may also sit on surface hoar in some places. At lower elevations, the snowpack will be rain-soaked.

The remainder of the snowpack is well-settled.

Watch North Shore Rescue's snowpack conditions update from Friday here.

Terrain and Travel

  • Watch for fresh storm slabs building throughout the day.
  • Use conservative route selection. Choose simple, low-angle, well-supported terrain with no overhead hazard.

Problems

Storm Slabs

An icon showing Storm Slabs

Heavy, wet snow and wind will likely create widespread and reactive storm slabs at upper elevations

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Very Likely

Expected Size

1 - 2

Loose Wet

An icon showing Loose Wet

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

Aspects: All aspects.

Elevations: Below Treeline.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Jan 3rd, 2021 4:00PM