Avalanche Forecast

Issued: Dec 18th, 2022 4:00PM

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

Avalanche Canada isnowsell, Avalanche Canada

Email

This is not your typical coastal mountain snowpack! A number of buried weak layers persist and will likely become more of a concern as the upper snowpack settles and gains cohesion. Deeper weak layers could potentially be triggered by small wind slabs on the surface.

Summary

Confidence

Moderate

Avalanche Summary

No new avalanches have been reported in the last few days.

If you head out into the mountains, please share your photos or observations on the Mountain Information Network. Your information helps us understand local conditions!

Snowpack Summary

Cold temperatures continue to facet the surface snow. These sugary crystals will be easily redistributed by the current cold, northerly winds into drifts and stiff wind slabs.

Concerns in the mid and lower snowpack are dominated by two weak layers:

  • A weak surface hoar layer buried in early buried December is 30-60 cm deep and looks to be a bigger problem in sheltered terrain at lower elevations. Professionals are closely tracking this layer as the overlaying snow settles and gains cohesion.

  • A widespread crust and facet layer from late November is buried 40-80 cm deep, found on all aspects and elevations.

Total snow depths remain low for December with about 90 to 140 cm at treeline and up to 200 cm in the alpine.

Weather Summary

Cold arctic air dominates the weather throughout BC this week. High uncertainty remains over the potential for snowfall starting Tuesday.

Sunday night

Clear. No precipitation. Temperatures around -25 C and generally light Northeast winds in the alpine.

Monday

Mostly clear with no precipitation. Temperatures -20 to -25 C and light Northeast winds in the alpine.

Tuesday

Mostly cloudy with potential for flurries. Temperatures around -20 C and light North winds in the alpine.

Wednesday

A mix of sun and cloud, with no precipitation. Temperatures -15 to -20 C and light Northeast winds.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
  • If triggered, wind slabs avalanches may step down to deeper layers resulting in larger avalanches.

Problems

Wind Slabs

An icon showing Wind Slabs

Cold, Northerly winds are redistributing the recent snow into potentially reactive windslabs. With cold temperatures windslabs will likely take longer then usual to stabilize and bond to the underlaying surfaces.

Remember that small wind slabs on the surface could scrub down to deeper weak layers in the snowpack, resulting in bigger then expected avalanches.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 2

Persistent Slabs

An icon showing Persistent Slabs

A number of weak layers have been buried in the mid snowpack, down roughly 40 to 100 cm from the surface. Watch as the overlaying snow gains cohesion and could make this layer much more reactive.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 2.5

Valid until: Dec 19th, 2022 4:00PM