Bulletin d’avalanche

South Coast

Apr 16 – 17, 2021Avalanche Canada
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Archivé · expiré 5 years ago

Danger d’avalanche

Sun
Mon
Alpin
3 · Marqué
Limite forestière
3 · Marqué
Sous la limite
3 · Marqué

Points saillants

Start (and finish) your day early and avoid exposure to sun-exposed avalanche terrain. Look for high elevation north facing objectives without cornices overhead, and plan your egress route carefully.

Check out the Forecaster's Blog for more on managing spring conditions.

Problèmes avalancheux

  • Cornices

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Likely
    Taille
    2–3

    Cornices are large and looming along many ridgelines. They become increasingly unstable during periods of warming.

  • Loose Wet

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Very Likely
    Taille
    1–2.5

    The snow will quickly lose cohesion and become unstable with sun and warm temperatures.

Confidence

Moderate - Confidence is due to a stable weather pattern with little change expected.

Weather Forecast

A ridge of high pressure, with sunny skies and high freezing levels continues to dominate the weather pattern this weekend.

Friday night - Clear / light east wind / alpine low temperature near 8 / freezing level 3200 m

Saturday - Sunny / light southwest wind / alpine high temperature near 10 / freezing level 3300 m 

Sunday - Sunny in the morning with increasing cloud throughout the day / moderate northeast wind / alpine high temperature near 7 / freezing level 3300 m, falling to 2500 m in the afternoon

Monday - Mainly sunny / light northeast wind / alpine high temperature near 3 / freezing level 2500 m

Avalanche Summary

There have been a few reports of wet loose avalanches and cornice failures in recent days.

Looking forward, wet loose avalanches and cornice failures are expected to continue with sun and warm temperatures. The likelihood and potential size of these increases when temperatures do not dip below freezing overnight, and avalanche activity will likely begin earlier in the day with each subsequent warm day. 

Wind slabs may still be possible to trigger on high elevation north aspects.

Snowpack Summary

The snow surface may be a crust in some areas, but recent high overnight freezing levels may mean that the snow surface is moist or wet in most areas. In places where the surface is a crust, sunshine and warm temperatures are expected to quickly soften the crust. High elevation north aspects may still have soft snow or wind slabs.

Cornices are large and looming along ridgelines. Their release is unpredictable, requiring a large berth if you're travelling above or below them. Sun and warm temperatures will increase the chances of cornice failures, especially when temperatures remain above zero overnight.

Terrain and Travel

  • The more the snowpack warms-up and weakens, the more conservative you`ll want to be with your terrain selection.
  • Avoid exposure to sunny slopes, especially in the afternoon.
  • Pay attention to cornices and give them a wide berth when traveling on or below ridges.
  • Avoid areas with overhead hazard, especially solar aspects.
  • Watch for wind-loaded pockets especially around ridgecrest and in extreme terrain.

Régions couvertes