Avalanche Forecast

Issued: Jan 4th, 2022 4:00PM

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

Avalanche Canada ghelgeson, Avalanche Canada

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The best riding and lowest hazard intersect in wind sheltered terrain below treeline. If you're stepping out into wind affected terrain, you'll likely find storm slabs that are sensitive to human triggering. Keep your terrain choices in check as the storm snow settles.

Summary

Confidence

Moderate -

Weather Forecast

Another storm is set to impact the region Thursday.

TUESDAY NIGHT: Overcast, freezing level at valley bottom, trace of snow possible, light variable wind.

WEDNESDAY: Broken cloud cover, daytime high temperature between -10 and -15 C at treeline, light wind generally out of the northwest, trace of snow possible.

THURSDAY: Overcast, daytime high temperature between -10 and -15 C at treeline, strong southwest wind, snow beginning in the morning, 5 to 15 cm expected during the day with another 5 to 15 cm expected Thursday night.

FRIDAY: Overcast, flurries, daytime high temperature between -10 and -15 C at treeline, strong west/southwest wind, 5 to 10 cm of snow possible.

Avalanche Summary

Lots of natural (and a few human triggered) storm slabs and loose dry avalanches to size two were observed Monday, primarily on northeast facing terrain.

In both the North and South Columbias avalanche activity on the early December crust/facet interface has really tapered over the last week. It has been confined to a couple of isolated avalanches in complex northeast facing alpine terrain. Two were explosive triggered, while one failed naturally. Each had wide propagation and ran several hundred metres. 

Cornice falls have triggered numerous slabs recently. Navigate around cornices carefully, both on ridgelines and on the slopes below.

Snowpack Summary

The weekend storm produced 20 to 50 cm of storm snow accompanied by wind that was quite variable, but mainly out of the south. Wind loading is suspected to be extensive in the alpine, but the bulk of the observations we're getting are from lower elevations.

We're actively monitoring the early December crust. In some places it's scoured and on the surface, while in wind loaded terrain features it can be found as deep as 150 cm below the surface. It consists of faceted grains above a bulletproof crust formed by the Atmospheric Rivers of early December. Avalanches failing on this interface have the potential to be very large. There has been isolated avalanche activity on this crust in the last week that seems to be confined to complex alpine terrain.  

The biggest concern is how it will behave next weekend as temperatures rise quite dramatically.

Terrain and Travel

  • If you are increasing your exposure to avalanche terrain, do it gradually as you gather information.
  • Keep in mind that human triggering potential persists as natural avalanching tapers off.
  • Be carefull around freshly wind loaded features.
  • Be aware of the potential for large avalanches due to the presence of a persistent slab.

Problems

Storm Slabs

An icon showing Storm Slabs

The weekend storm produced 20 to as much as 50 cm of storm snow with plenty of strong wind that was mainly out of the south. Your best terrain choice is going to be wind sheltered terrain at and below treeline. If you're stepping out into more complicated terrain you're likely to find significant wind loading and the potential for human triggered avalanches.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

1.5 - 2.5

Persistent Slabs

An icon showing Persistent Slabs

The early December crust can be found down 80 to 150 cm below the surface. While activity on this interface has really tapered off, it makes it difficult to have much confidence in stepping out into bigger terrain as avalanches failing on this layer have the potential to be large and destructive.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Unlikely - Possible

Expected Size

2.5 - 3.5

Valid until: Jan 5th, 2022 4:00PM