Bollettino valanghe

Northwest Coastal

Feb 3 – 4, 2015Avalanche Canada
Vedi sulla mappa
Archiviato · scaduto 12 years ago

Pericolo valanghe

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

In sintesi

Recent snowfall and strong winds are creating new problems. Solar inputs on Wednesday may elevate your local hazard. Assess the stability in your riding area before committing to avalanche terrain.

Problemi valanghivi

  • Persistent Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Possible
    Dimensione
    3–5
    The late-Jan crust is down 100-130cm and may still be reactive in some areas. In the mid-pack there are older persistent weak layers but these have generally stabilized. Extra caution is required in thinner snowpack areas, especially the north.

  • Storm Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Likely
    Dimensione
    1–3
    30-40cm of recent storm snow may be settling into a widespread storm slab. In exposed terrain, new wind slabs can be expected. Loose sluffing from steep terrain may also be a concern. Use extra caution on sun exposed slopes.

Confidence

Fair - Timing, track, or intensity of incoming weather system is uncertain

Weather Forecast

A ridge of high pressure should keep the North Coast mainly dry on Wednesday. A mix of sun and cloud is expected with freezing levels around 500m and moderate alpine winds from the SW-W. On Thursday, sub-tropical moisture will mix with arctic air resulting in moderate-to-heavy snowfall. Freezing levels should remain at or near valley bottom and alpine winds will become strong-to-extreme. Conditions on Friday should be much the same with heavy snowfall, valley bottom freezing levels, and strong-to-extreme winds.

Avalanche Summary

On Monday, skiers triggered a few size 1 to 1.5 storm slabs.  The size 1.5 avalanche released 40cm deep on a NE aspect at 1200m elevation. Sluffing from steep terrain was also reported. Some natural activity was reported on Monday in the NW Inland region. On Wednesday, natural avalanches are possible on sun exposed slopes or recently wind-loaded features. Skier-triggering is likely in wind loaded features and areas where the recent snowfall is settling into a cohesive slab.

Snowpack Summary

30-40cm of new snow has fallen in the last couple days. Strong winds have redistributed this snow in exposed terrain forming winds slabs in leeward features and stripping exposed slopes. The late-January crust is typically down 100-130cm in the south of the region and about half this depth in the north. Tests are indicating that this interface is generally well bonded but isolated avalanches have been reported to have released on this layer recently. The mid-January rain crust and/or surface hoar layer is down over 150cm in the south and has generally become inactive. It may still be a concern in thinner snowpack areas. The November crust/facet combo near the bottom of the snowpack is thought to be generally well bonded. However, this deep and destructive layer is still reported to be reactive in the far north of the region.

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