Avalanche Forecast

Issued: Jan 28th, 2023 4:00PM

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

Avalanche Canada dsaly, Avalanche Canada

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This challenging snowpack continues to produce avalanches. Stick to low-angle terrain away from any overhead hazard.

Read more in the latest Forecaster Blog.

Summary

Confidence

Low

Avalanche Summary

Both natural and human-triggered persistent and deep persistent slab avalanches continue to be reported daily. On Friday east of Prince George, skiers triggered a size 2 deep persistent avalanche on a northeast slope at 1700m, the avalanche was triggered from the shallowest portion of the feature and the crown depth varied from 30 cm to 1 m. Additionally, two very large (size 2.5-3) natural wind slabs were reported on northeast-east and southeast aspects around 1900 m.

On Thursday a few very large (size 2.5-3) natural wind slab avalanches were reported around 1800-2000 m. Additional ongoing evidence of weak basal facets continued with a size 3 deep persistent avalanche reported on a steep southeast slope at 2400 m.

On Monday, a fatal skier-triggered avalanche incident occurred in the Selkirk range near Revelstoke. The avalanche occurred on an east aspect at 1900 m, on a steep, open and unsupported slope. The size 2 avalanche had a crown depth of 50 cm and failed on surface hoar buried in early January.

Last weekend (Saturday), a fatal avalanche incident occurred in the Oasis riding area south of Valemont. This avalanche resulted in a rider fatality. This was a remotely triggered (from a distance) size 2.5 deep persistent slab avalanche on a north-northwest aspect at 2100 m. More details can be found here.

Avalanches like these are most likely to be triggered on steep, shallow and previously undisturbed slopes. Your best defence at this time is to stay diligent in choosing low-consequence terrain that has been heavily trafficked throughout the winter. Stay disciplined and adjust your expectation for this winter.

Snowpack Summary

20-40 cm recent snowfall covered a layer of surface hoar and thin crust on solar aspects at treeline and higher, and a supportive crust up to 1800 m. North and westerly winds have redistributed loose snow to lee terrain.

A prominent layer of buried surface hoar can be found roughly 40-70 cm deep. It is found in some places but not in others, and has been recently reactive to human triggering. The bottom of the snowpack is made up of large weak facets buried in late November, causing the Deep Persistent Slab problem for this region.

Weather Summary

Saturday night

Clear and with gusty ridgetop winds. Ridge wind northwest reaching 30 km/hr. Alpine temperature -24 C.

Sunday

Sunny in the morning with increasing clouds throughout the day. Ridge wind northwest 15-30 km/hr. Alpine temperature -20 C.

Monday

Sun and increasing cloud. Ridge wind southwest 15-30 km/hr. Alpine temperature rising to -16 C.

Tuesday

Flurries, 5-10 cm. Increasing southwest ridge wind 30-40 km/hr. Alpine temperatures rising to -12 C.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Be mindful that deep instabilities are still present and have produced recent large avalanches.
  • Approach lee and cross-loaded slopes with caution.
  • Avoid thin areas like rock outcroppings where you're most likely to trigger avalanches failing on deep weak layers.

Problems

Wind Slabs

An icon showing Wind Slabs

Recent northwesterly winds have redistributed recent snow and pressed surfaces. Expected continued transport and new slabs where wind impacts loose snow.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2

Persistent Slabs

An icon showing Persistent Slabs

A surface hoar layer is found 40-70 cm deep throughout the region and has been reactive in scattered areas around the region. Be especially cautious around steep openings treeline and below.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

1.5 - 2.5

Deep Persistent Slabs

An icon showing Deep Persistent Slabs

A layer of large and weak facets sits near the base of the snowpack. This layer has most recently been reactive in upper treeline/lower alpine elevations. Riders are most likely to trigger an avalanche on this layer in steep, shallow previously undisturbed terrain or by first triggering a layer further up in the snowpack.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

2 - 3

Valid until: Jan 29th, 2023 4:00PM