Avalanche forecast

Kootenay Boundary

Dec 10 – 11, 2014Avalanche Canada
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Avalanche danger

Fri
Sat
Alpine
3 · Considerable
Treeline
3 · Considerable
Below
2 · Moderate
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Highlights

Loading and warm temperatures will have a destabilizing effect on the snowpack. Watch your overhead hazard as weak layers may "wake-up" with the potential for large and destructive avalanches.

Avalanche problems

  • Persistent Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    3–5
    Warm temperatures and the load from rain may spark renewed destructive avalanche activity on weak layers near the base of the snowpack. "Whumpfing" has been reported throughout the region, indicating this layer is still ready for triggering.

  • Storm Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible - Likely
    Size
    1–3
    Dense and cohesive storm slabs are forming at higher elevations with the potential for wide propagations. Watch for triggering in lee terrain.

  • Loose Wet

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Likely
    Size
    1–3
    Rain may trigger further loose wet avalanche activity. Loose wet avalanches can be pushy and entrain mass quickly.

Confidence

Poor - Due to the number of field observations

Weather Forecast

The sub-tropical storm cycle will continue through Thursday bringing another round of moderate to locally heavy precipitation, strong southwest winds and freezing levels at about 2300m. As the system moves east on Friday there may be lingering light snowfall, light southwest winds and freezing levels at about 1500m. By Saturday a dry ridge should develop bringing clearing skies, light northwest winds and freezing levels at about 800m.

Avalanche Summary

Numerous size 1 loose wet avalanches were observed in the Kootenay Pass area on Tuesday. Although observations have been limited, I suspect this activity has been fairly widespread with the wet weather. Rain or loading from snow may also spark destructive avalanche activity on persistent weaknesses which exist near the base of the snowpack. If you have any avalanche observations, please share them on our new Mountain Information Network. For more details, go to: https://avalanche.ca/blogs/VIYBuScAAJdbdqPz/m-i-n-intro

Snowpack Summary

Rain has likely saturated and weakened the upper snowpack in most areas. The extent of saturation will depend on elevation and the amount of rain that fell. At upper elevations, precipitation may have fallen as moist snow, and may be adding load and cohesion to a storm slab which overlies a weak layer of facets, surface hoar, a hard rain crust or a combination thereof.Near the base of the snowpack is a crust/facet combination which is a concern at higher elevations in many parts of the region. This destructive layer continues to produce whumpfing, and may see a "wake-up" with warming and the load from rain or snow.

Regions covered