Avalanche Forecast

Issued: Dec 15th, 2023 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 but reactive wind slabs may linger around ridgelines and rollovers.

Summary

Confidence

Moderate

Avalanche Summary

On Thursday skier triggered storm slabs were reported, to size 1. Size 1- 1.5 natural wind slabs were observed in northwest facing features at 2000 m. These are suspected to have run on the crust buried 30 cm deep.

If you're heading out in the backcountry, please share any observations or photos on the Mountain Information Network.

Snowpack Summary

Winds have redistributed 10 cm of storm snow into deeper deposits on north and east facing slopes. This covers a 1-2 cm thick melt-freeze crust that extends well into the alpine. In sheltered areas, a layer of surface hoar may be found above the crust.

At treeline and above there are two layers of concern, buried around 40 and 60 cm deep. Both layers consist of a crust that tapers at higher elevations covered by a layer of fragile surface hoar in sheltered areas. No recent avalanche activity has been reported on these layers but they continue to be reactive in snowpack tests.

Overall, the snow depth remains relatively shallow, with numerous hazards present at or just below the snow surface across all elevations.

Weather Summary

Friday Night

Mainly cloudy with 5cm of snow possible, isolated to the NW corner of this region. Freezing levels drop to 1000 m. Southwest winds, 50-70 km/h.

Saturday

A mix of sun and cloud with up to 5 cm of snow possible west of Whistler. Freezing levels reach 1500 m, with treeline temperatures around 0 °C. Westerly winds, 20-30 km/h.

Sunday

Mainly sunny with no snowfall. Westerly winds, 20-30 km/h. Freezing levels spike to 2500 m in the afternoon, treeline temperatures of +3 °C.

Monday

Increasing cloud. Southwesterly winds, 30-50 km/h. Freezing levels remain above 2500 m overnight and through Monday, treeline temperatures of +3 °C.

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.
  • Wind slabs may be poorly bonded to the underlying crust.
  • Be alert to conditions that change with aspect and elevation.

Problems

Wind Slabs

An icon showing Wind Slabs

Wind slabs may continue to be reactive, especially where they sit over a crust or surface hoar.

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 1.5

Valid until: Dec 16th, 2023 4:00PM