Bulletin d’avalanche

Jasper

Avalanche Canada
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Danger d’avalanche

Sun
Mon
Alpin
2 · Modéré
Limite forestière
Conditions printanières
Sous la limite
Conditions printanières
Périmé — ce bulletin a expiré 4 months ago. Vous consultez des conditions passées, pas le bulletin en cours.

Points saillants

Spring is creeping up from the valley bottom into treeline and below treeline elevations, but winter conditions still exist in the alpine.

Solar input through the day will increase avalanche hazard, so plan to start and finish ski days early.

Problèmes avalancheux

  • Wind Slabs

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

    Soft snow and strong winds have created isolated pockets of wind slab in the high alpine. Assess for recent loading before committing to features.

  • Persistent Slabs

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Unlikely - Possible
    Taille
    1.5–3

    A persistent weak layer of facets is down 80–120 cm and may still be triggerable by humans in shallow areas, and by large loads like collapsing cornices or wet loose avalanches. This problem exists on all aspects, but has been most active on solar slopes.

  • Loose Wet

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Likely
    Taille
    1–1.5

    Slopes receiving direct sunlight can quickly warm up, even with cool air temperatures. Fresh snow sitting on top of a crust is likely to sluff.

Confidence

Moderate

  • We are uncertain about how the timing or intensity of warming will affect the snowpack.

Avalanche Summary

A size 2 slab avalanche was observed below the Athabasca Silverhorn on Wednesday morning, and another size 2 persistent slab avalanche on the endless chain was observed on Thursday morning. The age is uncertain for both of these avalanches but likely occurred approximately 48 hours prior to observation. There was no icefields road patrol on Friday.

Snowpack Summary

Fifteen centimeters of recent storm snow are sitting on preserved dry snow in the high North and is moist and settling on a variety of melt forms on solar slopes and at lower elevations. Below 2300m, multiple melt-freeze crusts are layered in the snowpack.

The January 24th layer is buried 80–120 cm deep and remains a lingering concern in the alpine. The lower snowpack is generally well consolidated in deeper areas, while shallow areas remain weaker and more faceted.

Weather Summary

Saturday

A mix of sun and cloud.

Precipitation: Nil.

Alpine temperature: High -2 °C.

Ridge wind west: 10-20 km/h.

Freezing level: 2100 metres.

Sunday

Cloudy with sunny periods.

Precipitation: Nil.

Alpine temperature: Low -4 °C, High 2 °C.

Ridge wind west: 15 km/h gusting to 40 km/h.

Freezing level: 2500 metres.

Monday

A mix of sun and cloud with isolated showers.

Precipitation: Trace.

Alpine temperature: Low 1 °C, High 6 °C.

Ridge wind west: 15 km/h gusting to 45 km/h.

Freezing level: 2900 metres.

Terrain and Travel Advice

  • Avoid sun-exposed slopes, especially if the snow surface is moist or wet.
  • Avoid freshly wind-loaded features, especially near ridge crests, rollovers, and in steep terrain.

Régions couvertes