Avalanche forecast

Banff Yoho Kootenay

Mar 4 – 5, 2019Parks Canada
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Avalanche danger

Tue
Wed
Alpine
2 · Moderate
Treeline
1 · Low
Below
1 · Low

Highlights

Clear sky's and warming temperatures this week will likely effect the upper snowpack. Watch for an increase in loose dry avalanche activity on solar aspects with daytime warming.

Avalanche problems

  • Wind Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Unlikely
    Size
    1–2
    A mix of fresh and old wind slabs have been stubborn but active, and are likely only to be found in very steep or extreme terrain near wind exposed ridge crests. Pay close attention to the feeling of the surface snow under your feet.
  • Loose Dry

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Likely
    Size
    1–2
    Cold weather has created weak, faceted surface snow. In steep terrain, these facets are easily triggered and can gain enough mass to affect skiers and climbers. Solar triggering of this problem will be come more of a concern over the next few days.

Weather Forecast

Hope on the horizon with warming temperatures approaching for the week. Evening temps for the start of the week will continue to be frigid with lows dipping in the mid -20's, but clear sky's and daytime highs around -5 will be a welcome change. With warming temps we can expect solar triggering to become more of a concern southerly aspects.

Snowpack Summary

Prolonged cold temperatures have weakened the upper snowpack. Wind effect is common in the alpine and several recent crusts can be found on steep solar slopes. Despite the weakening slab above it, Jan 17 surface hoar lingers down 40-60 cm in isolated locations and produces hard, resistent shears. A weak basal snowpack exists in thin snowpack areas.

Avalanche Summary

On a flight over the forecast region today we observed a few large triggers (cornice and seracs) impacting slopes below, causing only small avalanches given the size of trigger. The loose dry problem remains the main concern. We continue to see natural and human triggered avalanches out of most steep terrain.

Confidence

Timing or intensity of solar radiation is uncertain

Regions covered