Avalanche Forecast

Issued: Dec 24th, 2022 4:00PM

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

Avalanche Canada wlewis, Avalanche Canada

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Wind loaded features are the primary concern. Watch for wind slabs in sheltered terrain at lower elevations, strong winds may have redistributed snow lower than you would expect.

Reactivity will be greatest where they sit over a surface hoar layer.

Summary

Confidence

Moderate

Avalanche Summary

On Friday, wind slabs were reported to size one from natural and human triggers.

If you are heading into the backcountry please consider filling out a Mountain Information Network report.

Snowpack Summary

Strong westerly winds have redistributed recent snow into wind slabs at higher elevations. On south facing slopes wind slab could have formed over a sun crust. A layer of surface hoar down around 30cm can be found in sheltered terrain on all aspects up to 2000m. Reactivity will increase where wind slabs sit over this surface hoar, especially as temperatures increase on Monday and Tuesday.

A weak layer consisting of facets and a crust formed in November is now buried around 60cm deep.

In general, the snowpack is quite weak and faceted with average snowpack depths of around 150cm at treeline.

Weather Summary

Saturday Night

Partly cloudy with up to 5 cm of snow. Extreme westerly winds ease back to strong. Freezing level below 500 m.

Sunday

Mostly cloudy with light flurries bringing trace amounts of new snow. Moderate westerly winds. Freezing levels around 500 m, high temperatures of -3°C.

Monday

Cloudy with trace amounts of snow expected, or light rain. Strong southwest winds return. Freezing levels rise to 2000 m. High temperatures of +3 °C.

Tuesday

Wet snow and rain continues overnight with another 5 mm forecast, while freezing levels remain elevated around 1800 m.

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.
  • Be especially cautious as you transition into wind affected terrain.

Problems

Wind Slabs

An icon showing Wind Slabs

Strong to extreme westerly winds have likely stripped west facing slopes and deposited snow lower down on north and east facing slopes.

Watch for mid slope terrain features like rollovers. In sheltered terrain slabs may sit over a layer of reactive surface hoar.

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

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

1 - 2

Valid until: Dec 25th, 2022 4:00PM