Bollettino valanghe

Kootenay Boundary

Feb 16 – 17, 2025Avalanche Canada
Vedi sulla mappa
Archiviato · scaduto 2 years ago

Pericolo valanghe

Tue
Wed
Alta quota
2 · Moderato
Limite del bosco
2 · Moderato
Sotto il limite
2 · Moderato

In sintesi

Fresh wind slabs are forming on lee slopes and triggering persistent slabs remains possible.

Retreat to more conservative terrain if you experience signs of instability.

Problemi valanghivi

  • Wind Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Likely
    Dimensione
    1–1.5

    New snow combined with moderate winds are expected to form reactive new wind slabs in lee terrain. Be careful with wind-loaded pockets, especially near ridge crests and rollovers.

  • Persistent Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Possible
    Dimensione
    1–2

    A layer of surface hoar buried 20 to 60 cm has been reactive where a cohesive slab exists above it.

Confidence

Moderate

Avalanche Summary

On Friday a few naturally-triggered wind slabs were observed near Kootenay Pass from lee southerly slopes. A remotely-triggered slab was also observed there on a steep bank below treeline.

On Wednesday a rider remotely triggered a persistent slab avalanche (size 2) on an east-facing slope just above 2000 m. (See photo below)

Dry loose sluffing continues to be observed from steep terrain features.

Snowpack Summary

Exposed terrain in the alpine and treeline is variably wind-affected. Up to 10 cm of new snow is expected in some areas by the end of the day Sunday. This will add to a recent snowfall of around 5 cm, which is covering a layer of surface hoar in many areas, or a thin suncrust on steep south-facing slopes. Below that, 20 to 60 cm of faceted snow overlies a persistent weak layer from late January. This layer consists of a crust on sun-exposed slopes and surface hoar on all other aspects. Recent snowpack tests indicate that an overlying stiff and consolidated slab is generally required for it to be reactive. The remaining is generally well settled.

Weather Summary

Saturday Night

Cloudy with 2 to 5 cm of snow. 20 to 25 km/h south ridgetop wind. Treeline temperature -10 °C.

Sunday

Cloudy with 3 to 6 cm of snow. 15 to 30 km/h southwest ridgetop wind. Treeline temperature -9 °C.

Monday

Cloudy with 0 to 3 cm of snow. 15 km/h variable ridgetop wind. Treeline temperature -8 °C.

Tuesday

Sunny. 10 to 25 km/h northwest ridgetop wind. Treeline temperature -7 °C.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Be careful as you transition into wind-affected terrain.
  • Approach steep and open slopes at and below treeline cautiously, as buried surface hoar may exist.
  • Be aware of the potential for loose avalanches in steep terrain where snow hasn't formed a slab.
  • Watch for signs of instability like whumpfing, hollow sounds, shooting cracks, or recent avalanches.

Regioni coperte