Avalanche forecast

Northwest Coastal

Dec 22 – 23, 2024Avalanche Canada
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Avalanche danger

Tue
Wed
Alpine
3 · Considerable
Treeline
3 · Considerable
Below
1 · Low
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Highlights

Reactive wind slabs exist on all aspects at treeline and above.

Whumpfing, shooting cracks and avalanches are indicators of unstable conditions.

Avalanche problems

  • Wind Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible - Likely
    Size
    1–2

    Gusty winds are impacting any loose snow, variable winds may have reverse-loaded features. Watch for reactive deposits around ridges or lee features.

Confidence

Moderate

Avalanche Summary

Some helpful MIN reports from the Shames area describe numerous natural and skier triggered slab avalanches up to size 2. These were on southwest slopes at treeline. The early December crust buried 20 to 50 cm down is a suspect weak interface.

Reactive wind slabs may persist through Sunday.

Snowpack Summary

Recent strong winds have varied in direction, building reactive wind slabs on all aspects at upper elevations. In some areas surface hoar and/or facets are buried 10 to 20 cm below the surface snow. 30 to 50 cm of wind-affected snow rests on a thick rain crust. Reports from the Shames area have noted cracking and whumpfing in the upper snowpack which indicates that they layers require further investigation.

Treeline snow depth range from 200-280 cm. The lower snowpack has no layers of concern.

Weather Summary

Saturday night

Cloudy, with flurries 5 to 10 cm. 25 to 55 km/h southeast ridgetop wind. Treeline temperature -2 °C. Freezing levels 1000 m.

Sunday

Snow 5 to 15 cm. 35 to 70 km/h southeast ridgetop wind. Treeline temperature -3 °C. Freezing levels 700 m.

Monday

Snow 5 to 10 cm. 15 gusting to 65 km/h southeast ridgetop wind. Treeline temperature -2 °C. Freezing level 1000 m.

Tuesday

Snow 10 to 20 cm. 10 gusting to 80 km/h southeast ridgetop wind. Treeline temperature -1 °C. Freezing level 800 m.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Avoid freshly wind-loaded features, especially near ridge crests, rollovers, and in steep terrain.
  • Back off if you encounter whumpfing, hollow sounds, or shooting cracks.
  • If triggered, wind slabs avalanches may step down to deeper layers resulting in larger avalanches.

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