Avalanche Forecast

Issued: Dec 13th, 2022 4:00PM

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

Avalanche Canada ahanna, Avalanche Canada

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Wind slabs may remain reactive to rider triggers and a buried weak layer looms in the west and central parts of the region. Check out our latest blog for ways of managing persistent avalanche problems.

Summary

Confidence

Moderate

Avalanche Summary

While recent avalanche activity in the region has been limited to explosive triggered wind slabs size 1-2 in the east of the region, backcountry observations have been limited so far this season. If you do go out in the mountains, please consider contributing to the MIN.

In the neighboring regions where the November weak layer is buried deeper, reports of rider-triggered avalanche activity on this layer have been piling up daily. Unfortunately, this is more likely than not a sign of what is to come for the western parts of the region.

Snowpack Summary

20 cm of recent snow has been redistributed by previous strong westerly winds, forming wind slabs at most elevations. Soft snow may still be found in sheltered areas.

A concerning weak layer consisting of facets and surface hoar formed in November is now buried 45-65 cm deep. This layer has been producing large avalanches in neighboring regions and has shown reactivity in snowpack tests here. This one is definitely on our radar!

The lower snowpack consists of sugary and faceted snow, with a thick rain crust near the ground.

Total snowpack depths at treeline elevations are 75 to 155 cm.

Weather Summary

Tuesday night

Flurries bringing a trace of snow. Light northerly wind. Alpine low -13 C.

Wednesday

Flurries in the morning bringing a trace of snow then clearing in the afternoon. Light northerly wind. Alpine high -6 C.

Thursday

Sunny. Light northerly wind. Alpine high -9 C.

Thursday

Mostly sunny. Wind increasing to strong from the northwest. Alpine high -10 C.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Keep your guard up at lower elevations. Wind slab formation has been extensive.
  • Avoid steep, rocky, and wind effected areas where triggering slabs is more likely.
  • If triggered, wind slabs avalanches may step down to deeper layers resulting in larger avalanches.
  • Look for signs of instability: whumphing, hollow sounds, shooting cracks, and recent avalanches.

Problems

Wind Slabs

An icon showing Wind Slabs

Much of the region has been heavily wind affected. Wind slabs may remain triggerable by riders at all elevations.

Aspects: North, North East, East, South East, South, North West.

Elevations: All elevations.

Likelihood

Possible

Expected Size

1 - 1.5

Persistent Slabs

An icon showing Persistent Slabs

A buried weak layer of surface hoar and facets exists 40-70 cm deep and is showing reactivity in snowpack tests. Avalanches on this layer are possible where overlying snow has formed a cohesive slab due to wind or settlement.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1.5 - 2.5

Valid until: Dec 14th, 2022 4:00PM