Avalanche forecast

North Columbia

Mar 17 – 18, 2020Avalanche Canada
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Avalanche danger

Thu
Fri
Alpine
2 · Moderate
Treeline
2 · Moderate
Below
2 · Moderate
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Highlights

A stable weather pattern is forecast for the next few days. Minimize exposure to steep slopes facing the sun during the hottest part of the day.

Avalanche problems

  • Wind Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    1.5–2.5

    Recent moderate to strong wind blowing from a variety of directions has formed wind slabs on all aspects.

  • Persistent Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Unlikely - Possible
    Size
    1.5–3.5

    A weak layer of surface hoar is buried 60-100 cm deep. The distribution of this problem extends to all aspects and elevations, but north to east aspects near treeline have been a hot-spot for reactivity.

Confidence

High - Confidence is due to a stable weather pattern; little change is expected for several days.

Weather Forecast

MONDAY NIGHT: Cloudy with clear periods, light north wind, alpine temperature -8 C.

TUESDAY: Mix of sun and cloud, light northwest wind, alpine temperature -5 C, freezing level 1300 m.

WEDNESDAY: Mix of sun and cloud, light northwest wind, alpine temperature -10 C, freezing level 500 m.

THURSDAY: Mix of sun and cloud, light northwest wind, alpine temperature -6 C, freezing level 1000 m.

Avalanche Summary

Recent reports from this weekend show several natural wind slab avalanches ranging in size from 1.5 to 3 running in the alpine on northeast, south and southeast aspects at treeline and in the alpine. There were also several cornice failures on northerly aspects to size 2.5.

Snowpack Summary

Moderate to strong northeast wind has redistributed snow into alpine and tree line lee terrain. Recent new snow from last week may sit on a surface hoar layer and a sun crust on steep solar aspects. 

A widespread weak layer of surface hoar buried at the end of February is 60-100 cm deep. On solar aspects, this layer may sit over a crust. There is a low likelihood of triggering an avalanche on this layer, but the consequences of doing so would be high. Read more about surface hoar on our forecaster blog.

Terrain and Travel

  • If triggered, wind slabs avalanches may step down to deeper layers resulting in larger avalanches.
  • Be aware of the potential for large avalanches due to the presence of buried surface hoar.
  • Minimize exposure to steep, sun exposed slopes, especially when the solar radiation is strong.
  • Cornices become weak with daytime heating.

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