Bollettino valanghe

Northwest Coastal

Jan 27 – 28, 2023Avalanche Canada
Vedi sulla mappa
Archiviato · scaduto 4 years ago

Pericolo valanghe

Sun
Mon
Alta quota
3 · Marcato
Limite del bosco
2 · Moderato
Sotto il limite
1 · Debole

In sintesi

The danger rating may be decreasing, however, buried weak layers remain a primary concern. Avoid wind-loaded terrain, and rocky, shallow start zones.

Problemi valanghivi

  • Wind Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Possible
    Dimensione
    1–2

    At higher elevations (2000 m and above), where the recent precipitation fell as snow, strong southwest winds have formed windslabs on lee slopes and terrain features.

  • Persistent Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Possible
    Dimensione
    1.5–3.5

    A series of storms have added a significant load to buried weak layers in the upper meter of the snowpack. The primary layer of concern is a layer of surface hoar now buried 30-50 cm deep, is primarily found inland and most concerning in sheltered and shaded open slopes around treeline.

    The second layer is comprised of facets and/or surface hoar that was buried in late December. This layer is now down 70-120 cm. It has shown evidence of strengthening but remains on our radar.

Confidence

Moderate

Avalanche Summary

A widespread avalanche cycle occurred Wednesday, up to size 3. Both loose wet and wind slab releases have been reported. While it is suspected some of the avalanche activity likely stepped down to deeper weak layers.

Snowpack Summary

At higher elevations, above roughly 2000 m, new snow has been redistributed by strong southwest winds. At lower elevations expect to find a widespread rain crust on the surface or moist, saturated snow at low elevations that are still experiencing above-freezing temperatures.

A weak layer of surface hoar buried in early January is now down 70-100 cm. This layer is spotty in its distribution and is of greatest concern in sheltered and shaded openings at treeline.

Weak layers that were reactive over the Christmas and New Year's period have shown signs of bonding and gaining strength. These include a surface hoar layer buried on Dec 28 found 50 to 100 cm deep and a facet layer buried on Dec 23 found 70 to 120 cm deep.

Weather Summary

Thursday night

Cloudy with isolated flurries and trace accumulation. Treeline temperatures 0 to -5 C. Moderate northwest alpine winds. Freezing levels 1000 m.

Friday

Mostly sunny, with no precipitation. Treeline temperatures 0 to -5 C. Light north alpine winds. Freezing levels 500 m.

Saturday

Sunny, with no precipitation. Treeline temperatures -10 to -15 C. Light to moderate northeast alpine winds.

Sunday

Sunny, with no precipitation. Treeline temperatures -5 to -10 C. Light northeast alpine winds.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • If triggered, wind slabs avalanches may step down to deeper layers resulting in larger avalanches.
  • Avalanche hazard may have improved, but be mindful that deep instabilities are still present.

Regioni coperte