Bollettino valanghe

Purcells

Nov 30 – Dec 1, 2012Avalanche Canada
Vedi sulla mappa
Archiviato · scaduto 14 years ago

Pericolo valanghe

Sun
Mon
Alta quota
3 · Marcato
Limite del bosco
2 · Moderato
Sotto il limite
1 · Debole
Apri la mappa completa

In sintesi

Warm and wet weather continues. Snowfall amounts are variable across the region.

Problemi valanghivi

  • Persistent Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Possible
    Dimensione
    2–5
    Two problem layers exist: A surface hoar layer 30 - 60 cm below the snow surface and the early Nov. crust near the ground. It may be possible for a rider to trigger these weak layers, especially in areas where the snowpack is thin and/or rocky.

  • Storm Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Possible - Likely
    Dimensione
    1–4
    Storm slabs continue to grow in the alpine and at treeline from the warm wet weather. Snowfall amounts may be quite variable across the region. Watch for conditions that may be quite different at higher elevations due to recent high freezing levels.

Weather Forecast

Overnight and Saturday: The freezing level is expected to drop back down to the valley bottom overnight and then rise to about 1200 metres during the day. Continued waves of light precipitation are expected overnight and during the day. Moderate precipitation combined with moderate gusting to strong Southerly winds are forecast for Saturday.Sunday: The freezing level should lower to valley bottoms as the winds lighten and back to the South. Light precipitation is expected to continue as another wave of moisture is spun off of the Pacific Low that is anchored in the Gulf of Alaska.Monday: The next wave of wind and precipitation is expected to move into the region from the southwest. Forecast amounts are about 10 mm at this time.

Avalanche Summary

Some reports of loose natural avalanches up to size 1.0 from steep unsupported terrain on Thursday. The warm storm has probably changed this by Friday afternoon.

Snowpack Summary

The new storm has come in very warm, and snowfall amounts have been variable across the region. There may be a storm slab between 10-30 cm above surface hoar that was deposited earlier in the week. A deeper surface hoar layer we're calling the November 17th SH can be found down around 60 cm in depth. This layer has been quite a bit more reactive here than it has been in the Selkirks or even as close as the Roger's Pass. There is a rain crust near the ground that we're calling the early November crust. There are some facets below it, or it may appear as a sandwich of crusts and facets, but it's been reported  as unreactive at this time. There is still a sharp transition in snow depth from treeline to below treeline making back-country travel challenging under 1300 m in elevation.

Confidence

Fair - Forecast snowfall amounts are uncertain on Saturday

Regioni coperte