Bulletin d’avalanche

Sea To Sky

Apr 17 – 18, 2016Avalanche Canada
Voir sur la carte
Archivé · expiré 10 years ago

Danger d’avalanche

Tue
Wed
Alpin
Sans niveau
Limite forestière
Sans niveau
Sous la limite
Sans niveau

Points saillants

Spring Conditions. Sunny skies and very high freezing levels will increase the avalanche danger. The surface crust holds the snowpack together and may break down rapidly if there is no re-freeze Sunday night.

Problèmes avalancheux

  • Cornices

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Possible - Likely
    Taille
    3–6
    Strong solar radiation and high freezing levels will continue to test remaining cornices in the alpine. Watch your overhead hazard and avoid traveling beneath corniced ridges.
  • Loose Wet

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Possible - Likely
    Taille
    1–3
    Sunny skies and high freezing levels will weaken the surface snow on solar aspects. Shaded aspects in the alpine may warm up enough to release as loose wet avalanches.
  • Wet Slabs

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Unlikely - Possible
    Taille
    2–7
    The likelihood of wet slab avalanches will increase over the next few days with forecast high freezing levels and strong solar radiation. Be especially careful at mid and lower elevations where the entire snowpack is sloppy and unsupportive.

Weather Forecast

It looks HOT for the foreseeable future with no overnight temperature recovery expected.  MONDAY:  Freezing level holding at 3500m, very little wind except at ridgetop where strong southwest wind is expected, no precipitation, clear skies.  TUESDAY:  Freezing level holding at 3500m, light variable wind, no precipitation, few clouds.  WEDNESDAY:  Freezing level holding at 3500m, light variable wind, no precipitation, mostly clear skies.

Avalanche Summary

No new avalanches reported, but we have very few eyes and ears still in the mountains reporting. Most commercial operations in the region have finished their season and data is becoming sparse.

Snowpack Summary

Cornices remain a concern, in part because of the potential to trigger wet slab avalanches that run to valley bottoms. Monitoring the overnight freeze of the snow surface is very important. If the snow surface does not freeze overnight or if the crust is only a few cm thick, the effect of daytime heating and solar radiation will weaken the snowpack much more quickly than it would if there is a well frozen thick crust. This is because the crust must first melt before the sun can weaken the snowpack. With the warmest weather this year forecast, layers in the mid snowpack and near the ground have the potential to wake up and become active. While isolated and unlikely, avalanches would be very large. Glide cracks are widespread, active, and best avoided. Low elevation and thin snowpack areas have become isothermal, meaning the snowpack is 0 degrees Celsius throughout. An isothermal snowpack is more prone to full depth wet slab avalanches during the heat of the day, especially on steep, rocky faces.

Régions couvertes