Avalanche forecast

Kootenay Boundary

Apr 21 – 22, 2012Avalanche Canada
View on map
Archived · expired 14 years ago

Avalanche danger

Mon
Tue
Alpine
3 · Considerable
Treeline
3 · Considerable
Below
3 · Considerable

Avalanche problems

  • Cornices

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Likely
    Size
    1–5
    Rising freezing levels will weaken cornices. They can be destructive by themselves and can also trigger large avalanches on the slope below.
  • Loose Wet

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Very Likely - Certain
    Size
    1–5
    Watch for loose wet avalanche activity on steep terrain, particularly on rocky, sun-exposed slopes. Loose wet avalanches can accelerate and entrain mass quickly.
  • Wet Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible - Likely
    Size
    2–6
    As warm temperatures continue to penetrate the snowpack, wet slabs become more probable. Recently buried crusts and weaknesses buried deeper in the snowpack may provide suitable sliding layers for wet slabs.

Confidence

Fair - Timing or intensity of solar radiation is uncertain

Weather Forecast

Mostly clear skies are expected for Sunday and Monday. Freezing levels are expected to reach 3300m with moderate alpine winds from the southwest.

Avalanche Summary

No new avalanches have been reported from the region. This may speak more to the lack of professional observers at this time rather than actual conditions. I would expect wet natural avalanche activity on Sunday and Monday resulting from forecast rising freezing levels and solar input.

Snowpack Summary

Recently formed windslabs have most likely settled and gained considerable strength with the warm temperatures on Saturday, and in some places transitioned into wet slabs. Below this, spring weather has left us with wet grains or melt-freeze crusts at treeline and above while warm temperatures have continued to penetrate and weaken the isothermal snowpack at lower elevations. The mid-February buried surface hoar layer is down about 140-220 cm. The likelihood of avalanches failing on this layer has been very low due to cooler temperatures, however it may wake up with warming and the consequence continues to be very large destructive avalanches. Cornices in the region are very large and have may become weak with spring temperatures.

Regions covered