Bulletin d’avalanche

Sea To Sky

Jan 16 – 17, 2025Avalanche Canada
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Archivé · expiré 2 years ago

Danger d’avalanche

Sat
Sun
Alpin
2 · Modéré
Limite forestière
1 · Faible
Sous la limite
1 · Faible

Points saillants

Lingering wind slabs may remain reactive to human triggers in isolated locations below alpine ridgetops.

Minimize exposure to overhead hazards when solar radiation is strong.

Problèmes avalancheux

  • Wind Slabs

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Possible
    Taille
    1–1.5

    Reports of wind slab avalanche activity are decreasing however where windslabs overlie a weak layer of facets or surface hoar they may remain reactive to human triggering.

Confidence

High

Avalanche Summary

On Wednesday, several, size 1 and size 2 loose wet avalanches were reported, triggered by warm temperatures and solar input. As temperatures cool Wednesday night avalanche activity is expected to subside.

On Monday, a size 1 skier-triggered wind slab avalanche was reported on an east aspect at 1800 m. The wind slab overlay a layer of small surface hoar 25 cm deep.

Snowpack Summary

At 2200 m and below, a melt-freeze crust exists on all aspects. In the alpine and exposed treeline, this crust overlies wind-affected surfaces. On sheltered north aspects, the crust overlies faceted snow. Above 2200 m dry snow may remain preserved on northerly aspects.

10 to 30 cm down is a small weak layer of surface hoar or facets. This layer remains a concern in isolated areas where a wind slab overlies it.

An otherwise right-side-up snowpack appears to be bonding well to a crust buried 70 to 100 cm deep. The mid and lower snowpack is generally well-settled and bonded with no layers of concern.

Weather Summary

Wednesday Night

Increasing cloud. 35 to 45 km/h southwest ridgetop wind. Treeline temperature -4 °C. Freezing levels drop to 900 m.

Thursday

Cloudy with light flurries, 1 cm. 15 to 25 km/h northwest ridgetop wind. Treeline temperature -7 °C. Freezing levels drop to the valley bottom.

Friday

Mainly sunny. 20 to 25 km/h northerly ridgetop wind. Treeline temperature -6 °C.

Saturday

Increasing cloud. 10 to 20 km/h northwest ridgetop wind. Treeline temperature -7 °C.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Carefully evaluate steep lines for wind slabs.
  • Avalanche activity is unlikely when a thick melt-freeze crust is present on the snow surface.
  • A hard crust on the snow surface will help strengthen the snowpack, but may cause tough travel conditions.

Régions couvertes