Bollettino valanghe

Purcells

Dec 5, 2018Avalanche Canada
Vedi sulla mappa
Archiviato · scaduto 8 years ago

Pericolo valanghe

Thu
Fri
Alta quota
2 · Moderato
Limite del bosco
1 · Debole
Sotto il limite
1 · Debole

In sintesi

Wind slabs may be more reactive where they sit above a buried weak layer. Field observations are limited, so it is important to supplement this forecast with your own observations. If you get out, tell us what you see by posting to the MIN! (here)

Problemi valanghivi

  • Wind Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Possible
    Dimensione
    1–2
    Wind slabs are most likely found on leeward slopes. They will likely be more reactive where they sit above a weak feathery surface hoar layer and/or a sun crust.
  • Deep Persistent Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Unlikely - Possible
    Dimensione
    1.5–3
    A combination of crust and faceted (sugary) snow exists at the base of the snowpack. This layer could produce avalanches on steep, smooth slopes in the alpine.

Confidence

Moderate - Due to the number of field observations

Weather Forecast

TUESDAY NIGHT - Clear periods / light to moderate northerly winds / alpine low temperature -14WEDNESDAY - Sunny with cloudy periods / light easterly winds / alpine high temperature -12THURSDAY - A mix of sun and cloud / light westerly winds / alpine high temperature -6, low temperature -11FRIDAY - Sunny with cloudy periods / light southerly winds / alpine high temperature -5, low temperature -9

Avalanche Summary

One size 1.5 wind slab avalanche was reported on a steep, cross loaded, rocky, north facing feature. Trigger type and elevation are unknown.Field observations in this region are very limited. If you have been in the backcountry, please submit your observations to the Mountain Information Network (MIN)

Snowpack Summary

The early season snowpack is highly variable in the Purcells. Approximately 20 cm of snow fell last week which may have been blown into wind slabs on exposed north and northeast facing slopes. There are two layers of surface hoar (weak feathery crystals) being reported in the top 15-30cm. The surface hoar is most prominent at treeline, but it may be found in sheltered alpine areas. Both of these layers may be associated with a sun crust on south aspects in some areas.A prominent feature of the snowpack is a combination of a crust and faceted (sugary) snow found at or near the base of the snowpack. This layer mainly exists in the alpine but it may be found at upper treeline elevations as well.Total snowpack depths vary greatly throughout the region with anywhere between 70 and 150 cm in the alpine and tapering rapidly at treeline and below. In shallow snowpack areas, the bottom half of the snowpack is reportedly weak and "hollow" feeling on shady aspects due to sugary, faceted snow.

Regioni coperte