Bollettino valanghe

Northwest Inland

Dec 25 – 26, 2022Avalanche Canada
Vedi sulla mappa
Archiviato · scaduto 4 years ago

Pericolo valanghe

Tue
Wed
Alta quota
3 · Marcato
Limite del bosco
3 · Marcato
Sotto il limite
2 · Moderato
Apri la mappa completa

In sintesi

Newly formed wind slabs are expected to be touchy on Sunday. These wind slabs likely sit over a weak layer which may increase their size and reactivity. Extra caution and conservative terrain selection are recommended at higher elevations.

Problemi valanghivi

  • Wind Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Likely - Very Likely
    Dimensione
    1–2

    New wind slabs have formed as new snowfall continues to be redistributed by ongoing strong southwest winds. Where these new wind slabs overlay a weak layer of sugary facets, increased reactivity should be expected and the slabs may propagate wider than normally expected.

    Older hard wind slabs from last week's northeast outflow wind event may still be reactive, but this is likely becoming an isolated problem. However, it is safest to assume wind slabs could exist on all aspects in wind-exposed terrain.

Confidence

Moderate

Avalanche Summary

On Friday afternoon, the Avalanche Canada field team reported ski-cutting a few size 1 avalanches on a north aspect convex roll feature at 1600 m elevation in the Hankin-Evelyn area. These failed on the old, hard surfaces and encompassed up to 25 cm of the recent storm snow. In the far south of the region, ski-cutting at below-treeline elevation was also triggering 10-15 cm thick slabs which were failing on a weak layer of facets.

Snowpack Summary

The new snow has buried a highly variable surface from the recent period of cold temperatures and outflow winds. The old wind-affected surface was generally very hard and in many places, the snow had been stripped to the ground. In sheltered areas around treeline, faceting had been observed and the snow surface was becoming unconsolidated.

Prior to the new storm snow, a layer of surface hoar could be found down 20 to 30 cm at treeline but had not been an active layer of concern.

Generally, the snowpack is shallow and highly variable in terms of depth, with the mid and lower snowpack presenting as settled and dense.

Weather Summary

A series of Pacific storm systems continue to impact the coast but only limited amounts are forecast to push into the inland regions.

Saturday night

Snowfall 5-10 cm, moderate to strong SW wind, treeline low around -12 °C.

Sunday

Snowfall 5-10 cm in the afternoon, moderate to strong SW wind, treeline high around -6 °C.

Monday

Snowfall around 5 cm, moderate to strong S-SW wind, treeline high around -6 °C.

Tuesday

Mainly cloudy with a chance of sunny breaks, moderate E wind, treeline high around -8 °C.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
  • Recent wind has varied in direction so watch for wind slabs on all aspects.
  • The best and safest riding will be on slopes that have soft snow without any slab properties.

Regioni coperte