Bulletin d’avalanche

Jasper

Mar 12 – 13, 2020Parks Canada
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Archivé · expiré 7 years ago

Danger d’avalanche

Sat
Sun
Alpin
3 · Marqué
Limite forestière
2 · Modéré
Sous la limite
1 · Faible

Points saillants

Fresh powder in the trees and out of the arctic wind may be the best option for the next few days.

Problèmes avalancheux

  • Wind Slabs

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Possible
    Taille
    1–2.5

    The wind slabs which formed earlier in the week appear to be bonding well. The forecasted new snow for Friday may well form weakly bonded wind slabs with the dramatic temperature drop and easterly winds.

  • Loose Dry

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Possible - Likely
    Taille
    1–2

    There is significant loose snow clinging to rock faces and in steep alpine features. Forecasted new snow will add to this.Triggering of this snow includes wind and solar radiation. Once off and running the debris may trigger deeper instabilities.

  • Deep Persistent Slabs

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Possible
    Taille
    2–3.5

    2 Large avalanches were observed on March 11th. Initiating this layer is more likely from large loads such as cornice fall or from shallow snowpack areas. In the valley bottom the snowpack is less consolidated with less chance of large releases.

Weather Forecast

The arctic air is approaching with an expected 5-10cm of snow overnight in the Icefields area, lesser amount to the north. The winds will switch to the E with this new air mass providing some reverse loading on westerly facing slopes. More detailed forecast at: Mountain weather forecast

Snowpack Summary

The Icefields area has a well bridged midpack overlying basal facets and depth hoar. The northern region is weaker with less bridging midpack above the basal facets and depth hoar.The fridge air will make for weak bonding of the new snowfall.

Sun crusts are largely absent and the melt is evident in the valley bottom with rocks starting to appear.

Avalanche Summary

On Wednesday a field team at the Columbia Icefields noted two Deep persistent avalanches up to size 3.5 on SW & NE aspects in the alpine. Cornices loom large and threatening over enticing terrain below but may also be the trigger for the deep persistent weakness. Spindrift and point releases avalanches have also been observed in the past week.

Confidence

The weather pattern is stable on Saturday

Régions couvertes