Bulletin d’avalanche

Northwest Inland

Mar 11, 2017Avalanche Canada
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Archivé · expiré 10 years ago

Danger d’avalanche

Sat
Mon
Alpin
3 · Marqué
Limite forestière
2 · Modéré
Sous la limite
2 · Modéré
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Points saillants

Danger will ramp up over the next few days with new snow, strong winds, and warming temperatures in the forecast. Stick to sheltered supported terrain.

Problèmes avalancheux

  • Wind Slabs

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Likely
    Taille
    1–2
    Gusty winds from the southeast have formed fresh wind slabs. Wind slab reactivity may persist for longer than usual due to underlying persistent weaknesses.

  • Deep Persistent Slabs

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Unlikely - Possible
    Taille
    2–3
    A lingering weakness at the bottom of the snowpack may remain sensitive to human triggering, especially in shallow snowpack areas. Smaller avalanches in motion also have the potential to step down and trigger destructive deep persistent slabs.

Confidence

Moderate - Timing, track, or intensity of incoming weather system is uncertain

Weather Forecast

SATURDAY: Flurries starting in the morning with 3-5 cm of new snow, 20-40 km/h southeast winds, alpine temperatures around -15 C.SUNDAY: Stormy with 5-10 cm of new snow, 40-60 km/h southwest winds, alpine temperatures climbing to -5 C.MONDAY: Another 5-15 cm of snow, 60-80 km/h southwest winds, alpine temperatures around -2 C and freezing levels climb to 1200 m.

Avalanche Summary

No new avalanches were reported in the southern part of the region on Thursday. A few size 2.5 natural wind slabs were reported around Ningunsaw.Wind slab activity will likely increase over the weekend with new snow and strong winds. Warming temperatures next week will likely stress deep persistent slabs.

Snowpack Summary

Generally light daily amounts of low density snow have fallen in recent days. Strong and variable winds have likely formed wind slabs in exposed terrain. These daily accumulations have incrementally loaded a weak interface which was buried in February. This buried layer includes stiff wind slabs, facets, crusts and surface hoar. The overlying slab may have a poor bond to these interfaces, especially in areas where the slab may be stiffer and more cohesive due to winds. At treeline, the average snowpack depths are 120-190 cm and a well consolidated mid-pack of approximately up to 100 cm sits above weak basal facets (sugary snow) near the ground. The deeper basal weakness remain a concern, especially in thin rocky start zones and shallow snowpack locations.

Régions couvertes