Avalanche forecast

Northwest Coastal

Dec 30 – 31, 2013Avalanche Canada
View on map
Archived · expired 13 years ago

Avalanche danger

Wed
Thu
Alpine
3 · Considerable
Treeline
3 · Considerable
Below
2 · Moderate
Open full map

Highlights

Avalanche problems

  • Persistent Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    2–6
    Primarily a concern in Northern sections. A recently buried surface hoar layer, now down 60-80 cm, could be triggered by additional loading from snow or wind or by the weight of a rider. Also, a weak facet/crust combo lurks near the ground.

  • Storm Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Likely
    Size
    1–5
    ~30cm of new snow has fallen since Sunday. Use increased caution where wind slabs have formed in exposed lee (N-SE) and cross-loaded terrain.

Confidence

Fair - Intensity of incoming weather systems is uncertain

Weather Forecast

Unsettled conditions and light precipitation are expected on Tuesday before the next major system reaches the North Coast on Wednesday.  Tuesday: Mostly cloudy, light precipitation 4-8cm, freezing level around 400m, moderate SW windsWednesday: Snowfall 15-25cm, freezing levels around 500m, moderate to strong SW windsThursday: A mix of sun and cloud, light flurries possible in the morning, light W winds

Avalanche Summary

No recent natural avalanches have been reported.  On Sunday, numerous explosive triggered storm avalanches were reported up to size 2.5.

Snowpack Summary

Southern Sections: The latest weather system dropped another 30 cm of snow, bringing the total snowfall over the past week to around 150 cm. The recent storm snow is likely "upside down" feeling, with heavier snow on top due to warming at the tail end of the system. Winds were also very strong from the SW most likely creating fresh wind slabs in exposed lee terrain at all elevations. Freezing levels climbed to near 1500 m resulting in moist snow or rain below treeline. Much of the low elevation snowpack has been washed away by recent rain.Northern Sections: Weaknesses may still exist within the recent storm snow which is now totalling over 80cm in the last week. Fresh dense wind slabs are likely in exposed lee terrain and cross-loaded features at all elevations. A recently buried surface hoar layer is now down around 80 cm and is likely primed for rider triggering. A facet/crust layer exists near the base of the snowpack, primarily on higher NW through E facing slopes. Triggering this layer may be unlikely, but if triggered the resulting avalanche would be very large and dangerous.

Regions covered