Avalanche Forecast

Issued: Jan 28th, 2021 4:00PM

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

Avalanche Canada kdevine, Avalanche Canada

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A widespread weak layer has been responsible for numerous recent avalanches. This problem is not going to disappear quickly. 

Stick to simple terrain and avoid overhead hazard.

Summary

Confidence

High - The snowpack structure is generally well understood. The number, quality, or consistency of field observations is good, and supports our confidence.

Weather Forecast

THURSDAY NIGHT - Mainly cloudy with a few flurries / light southwest wind / alpine low temperature near -2 

FRIDAY - Mainly cloudy with isolated flurries / light to moderate southwest wind / alpine high temperature near -2 

SATURDAY - Snow, 10-20 cm, with another 10 cm overnight / strong south wind / alpine high temperature near -1 

SUNDAY - Snow, 30-40 cm, with another 20 cm overnight / strong south wind / alpine high temperature near -1

Avalanche Summary

Human triggered avalanches are expected to be likely in many areas.

There have been numerous avalanches reported in the region everyday since Monday. These have been natural, human and explosives triggered storm slab avalanches failing on a prominent weak layer that is down 30-60 cm. A few recent MIN reports of some of these avalanches can be viewed here and here.

North Shore Rescue responded to a serious, but non-fatal avalanche incident on Tuesday evening in the backcountry near Cypress Mountain Resort. One person was involved and was partially buried. The avalanche was a size 2 storm slab on a west aspect at approximately 1100 m. This avalanche also failed on the recently buried weak layer.

Snowpack Summary

30-60 cm of recent fresh snow sits on a crust that also has weak facets and surface hoar on top of it in many areas. This weak layer is widespread and will probably take more time to gain strength than what is considered typical for the South Coast region. 

Click here to watch North Shore Rescue's January 22 snowpack discussion, which includes a great explanation of how the recently buried weak layer was formed.

Terrain and Travel

  • Use conservative route selection. Choose simple, low-angle, well-supported terrain with no overhead hazard.
  • Keep your guard up at lower elevations. Storms slabs have been reactive at all elevations.
  • Be aware of the potential for large avalanches due to the presence of buried weak layers.

Problems

Storm Slabs

An icon showing Storm Slabs

30-60 cm of recent fresh snow sits on a widespread weak layer that consists of a crust, with facets and/or surface hoar on top of it. This weak layer may continue to produce avalanches for longer than what is typical after a storm on the South Coast.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

1 - 2

Valid until: Jan 29th, 2021 4:00PM