Boletín de aludes

Northwest Inland

Jan 3 – 4, 2012Avalanche Canada
Ver en el mapa
Archivado · caducó 15 years ago

Peligro de aludes

Thu
Fri
Alta montaña
4 · Fuerte
Límite del bosque
3 · Notable
Bajo el límite
3 · Notable
Abrir el mapa completo

Problemas de aludes

  • Wind Slabs

    • Alta montaña
    • Límite del bosque
    • Bajo el límite del bosque
    Probabilidad
    Likely - Very Likely
    Tamaño
    2–5
    Strong southwesterly winds continue to set up touchy wind slabs on mainly north through east aspects.

  • Persistent Slabs

    • Alta montaña
    • Límite del bosque
    • Bajo el límite del bosque
    Probabilidad
    Possible - Likely
    Tamaño
    3–7
    Persistent slabs are getting harder to trigger but still exist in many locations. The probability of triggering has decreased, but the consequences of a release remain high.

  • Storm Slabs

    • Alta montaña
    • Límite del bosque
    • Bajo el límite del bosque
    Probabilidad
    Very Likely
    Tamaño
    2–6
    New snow with rising temperatures will set up storm slabs on steep, open slopes.

Confidence

Good - -1

Weather Forecast

An intense storm will bring moderate to local heavy amounts of precipitation-expect around 15-20 mm Tuesday night and a further 5-15 mm on Wednesday. Freezing levels will rise to around 1500 m and then start to fall on Wednesday afternoon as a cold front passes over. The passage of the cold front is unlikely to bring only light precipitation to inland areas, say 5 mm. Ridgetop winds will be extreme (up to 140 km/h) initially from the southwest, then becoming westerly. On Friday, another frontal system hits the north coast; however it looks as though northwest inland areas will be influenced by a ridge of high pressure keeping things mainly dry and cold.

Avalanche Summary

High winds and poor visibility have limited observations for the last few days; however, no activity has been reported to us from this region recently. I suspect you could easily trigger a pocket of wind slab on exposed lee terrain and I'd still be nervous of triggering the mid-December surface hoar layer down around 70 cm in sheltered locations.

Snowpack Summary

New snow and strong winds have set up fresh wind slabs mainly on north through east aspects in exposed lee terrain--these are likely triggerable by riders on sleds or on skis. There is now approximately 80 to 120cms of storm snow sitting above a surface hoar/crust/facet layer that was buried mid-December. The increasing depth of this weak layer makes it difficult to trigger; however, I wouldn't ignore this layer yet, as it could still be triggered by large loads such as rapid loading by new snow or rain or cornice falls. It could also be triggered by riders in shallow snowpack areas or where rocks poke up near the surface. The mid- and lower snowpack layers are well consolidated and generally strong.

Regiones cubiertas