Avalanche Forecast

Issued: Jan 12th, 2021 3:00PM

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

Avalanche Canada JMackenzie, Avalanche Canada

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A significant storm is set to arrive Tuesday night into Wednesday morning. Avalanche hazard will rise rapidly. Avoid avalanche terrain.

Summary

Confidence

Moderate -

Weather Forecast

A Pineapple Express is pushing into the region Tuesday evening and into Wednesday. Between 30 and 40cm of new snow is expected with SW winds up to 120km/h and freezing levels near 1900m. A cooling and clearing trend are expected Thursday.

Avalanche Summary

Ski cutting in steep terrain below treeline produced small sluffs. A size 1.5 wind slab was observed coming off a treeline feature on the south aspect of Heros' Knob. Further details are unknown as the skies were somewhat obscured.

Snowpack Summary

3cm of new snow fell in the past 24hrs. The extreme SW winds continue, and have created widespread wind slabs at all elevations on south, north and east aspects. Only the most sheltered areas below treeline have escaped this. Today forecasters dug a pit at treeline and discovered multiple wind slab layers that all produced sudden planar failures at the different interfaces. In addition, ski cutting produced surface sluffing in steep sheltered terrain below treeline today indicating that the new snow is not bonding well to the old surface. If the forecasted snow arrives, these observations indicate that a natural avalanche cycle will occur at all elevations.

Terrain and Travel

  • Avoid all avalanche terrain during periods of strong wind.
  • Avoid areas where the snow feels stiff and/or slabby.
  • Be alert to conditions that change with elevation and wind exposure.
  • Watch for fresh storm slabs building throughout the day.

Problems

Storm Slabs

An icon showing Storm Slabs

Strong westly winds with the incoming snow will create new storm slabs. 

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Very Likely

Expected Size

1.5 - 3

Wind Slabs

An icon showing Wind Slabs

This problem refers to the many generations of previously formed wind slabs. With the incoming storm, the numerous old wind slab interfaces will become reactive.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Very Likely

Expected Size

1.5 - 3

Valid until: Jan 13th, 2021 3:00PM