Boletín de aludes

South Columbia

Dec 3, 2018Avalanche Canada
Ver en el mapa
Archivado · caducó 8 years ago

Peligro de aludes

Tue
Wed
Alta montaña
2 · Moderado
Límite del bosque
2 · Moderado
Bajo el límite
1 · Débil
Abrir el mapa completo

Lo esencial

Waiting for a persistent slab to stabilize isn't fun, but it's better than getting caught pushing the conditions. Uncertainty exists with the reactivity of the buried weak layers. Check out the Forecaster Blog here.

Problemas de aludes

  • Persistent Slabs

    • Alta montaña
    • Límite del bosque
    • Bajo el límite del bosque
    Probabilidad
    Possible
    Tamaño
    1–2
    40 to 80 cm of recent storm snow overlies a weak layer of surface hoar (feathery crystals) and sun crust on steep south facing slopes. This problem may be more prevalent at treeline and in sheltered (northerly) alpine slopes.

  • Deep Persistent Slabs

    • Alta montaña
    • Límite del bosque
    • Bajo el límite del bosque
    Probabilidad
    Possible
    Tamaño
    2–3
    A crust at the base of the snowpack will result in large avalanches if triggered. Smaller avalanches, cornice and/ or rockfall may have the potential to step down to the basal layer.

Confidence

Moderate - The weather pattern is stable

Weather Forecast

MONDAY: Mix of sun and cloud/ alpine temperatures near -10/ generally light winds from the northeast/ freezing level valley bottomTUESDAY: Mix of sun and cloud/ alpine temperatures near -12/ ridgetop winds light with strong gusts from the northwest/ freezing levels valley bottomWEDNESDAY: Mix of sun and cloud/ alpine temperatures -12/ ridgetop winds light from the northeast/ freezing levels valley bottom.

Avalanche Summary

On Saturday, a natural solar triggered avalanche cycle occurred mostly from steep solar aspects up to size 1.5. A natural size 3 slab avalanche was seen on Mt. Begbie (ENE aspect above 2000 m). We suspect the triggered to be rockfall or a cornice above the slope. This avalanche may have failed on the basal crust.Last Saturday, a human triggered size 3 avalanche was reported in the region. This avalanche likely ran on the October crust, as it was reported as a full depth avalanche. Two reports on this avalanche can be found on the Mountain Information Network.

Snowpack Summary

40-80 cm of recent snow sits on two layers of feathery surface hoar that are approximately buried 15 cm apart. One or both of these may be associated with a crust on south aspects. The surface hoar is mostly found at treeline, but it may be found in sheltered alpine areas. Snowpack test results on these layers are showing a variety of planar results which indicate that this interface may be susceptible to human triggers.At the base of the snowpack is a crust that formed near the end of October. This crust is associated with sugary weak faceted crystals and has shown some reactivity in the South Columbia region. Suspect slopes and terrain are open bowls that host a rocky thin to thick snowpack in the alpine or upper treeline. Snowpack depths taper quickly with elevation, many areas have over 200 cm in the alpine, between 100-170 cm at treeline, and 10-100 cm below treeline.

Regiones cubiertas