Avalanche Forecast

Issued: Dec 17th, 2022 4:00PM

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

Avalanche Canada wlewis, Avalanche Canada

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Small slabs will form in wind affected terrain features as snow accumulates. Expect reactivity, slabs form over a surface hoar and crust combination.

The crust created by Friday's warming will be an ideal sliding surface for avalanches.

Summary

Confidence

Moderate

Avalanche Summary

No new avalanches have been reported in the past few days. We expect small slabs to be possible to trigger as they develop over Saturday and Sunday.

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

Surface conditions consist of large surface hoar sitting over a widespread melt freeze crusts.

40-70 cm of recent snow is settling, sitting over crusts on sun affected slopes, surface hoar in shaded areas or graupel in some locations. The mid and lower snowpack consists of layers of well bonded snow and melt freeze crusts.

At 1000 m the snowpack depth reaches 100-150 cm. In many areas, below treeline elevations are still below the threshold for avalanches.

Weather Summary

An Arctic front dominates the weather over BC. Light snowfall is expected Saturday night as a low south of Vancouver Island briefly competes with the cold air.

Saturday Night

Mainly cloudy with light snowfall delivering up to 5-8 cm. Freezing level around 300 m. Moderate to strong northwest winds.

Sunday

A mostly cloudy with light to moderate westerly winds. Freezing level below valley bottom, alpine high of -5°C. Another 5-10 cm of snow possible over the day. Snow and wind values increase as you move up the Fraser Valley and the Coquihalla.

Monday

Mostly cloudy with moderate westerly winds. Freezing level remains below valley bottom, expect an alpine high of -10°C. Isolated flurries.

Tuesday

Cloudy with moderate to strong westerly winds. Freezing level below valley bottom. Alpine high -8 °C. Moderate to heavy snowfall.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Make observations and assess conditions continually as you travel.
  • Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
  • Wind slabs may be poorly bonded to the underlying crust.

Problems

Wind Slabs

An icon showing Wind Slabs

New snow combined with northwest winds provides fresh potential for reactive wind slabs to build. Wind loading will sit over a crust and surface hoar.

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

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 2

Valid until: Dec 18th, 2022 4:00PM