Boletín de aludes

South Rockies

Jan 3 – 4, 2015Avalanche Canada
Ver en el mapa
Archivado · caducó 12 years ago

Peligro de aludes

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

Lo esencial

If Sunday's winds are stronger than forecast, the Avalanche Danger in the alpine may rise to Considerable. Watch for blowing snow at high elevations.

Problemas de aludes

  • Wind Slabs

    • Alta montaña
    • Límite del bosque
    • Bajo el límite del bosque
    Probabilidad
    Possible
    Tamaño
    1–3
    Between 15 and 30 cm of low-density snow has been transported by strong swirling winds into hard wind slabs. Initially winds blew from the northwest, but then switched to the southeast, which means wind slabs may be found on a variety of aspects.

  • Persistent Slabs

    • Alta montaña
    • Límite del bosque
    • Bajo el límite del bosque
    Probabilidad
    Possible
    Tamaño
    2–5
    A crust which formed in December should remain on your radar as it has recently produced large avalanches in the south of the region.  Dig down and test weak layers before committing to a line.

Confidence

Fair - Due to the number of field observations

Weather Forecast

On Sunday we can expect very light flurries, moderate northwesterly ridgetop winds, and alpine temperatures of about -18.  Light snowfall is expected by Sunday night, and should continue until Tuesday as a pacific frontal system pushes eastward. With this system, we can expect strong westerly winds with freezing levels staying at valley bottom.

Avalanche Summary

No new avalanches have been reported, although I suspect there was some wind slab activity in response to Friday's wind event.

Snowpack Summary

Snow surfaces are variable with northerly, wind exposed aspects showing firm wind pressing, or a scoured exposed crust. More sheltered locations have up to 30 cm of low density, faceted snow. In the alpine and at treeline, strong northerly winds have transported this snow into stiff wind slabs on opposite slopes. Up to 70 cm below the surface you will likely find a hard, thick crust which formed mid-December. At higher elevations this crust has facets (sugary) snow above it and well-preserved surface hoar up to 10 mm in size in sheltered locations at treeline and below. Where the crust exists, it may be bridging triggers from penetrating to deeper persistent weaknesses. However, on high alpine slopes above where the rain crust formed, or in areas where rain didn't occur, deeply buried facets may still be susceptible to triggering, especially in thinner snowpack areas.

Regiones cubiertas