Bollettino valanghe

Banff Yoho Kootenay

Mar 12 – 13, 2023Avalanche Canada
Vedi sulla mappa
Archiviato · scaduto 4 years ago

Pericolo valanghe

Tue
Wed
Alta quota
4 · Forte
Limite del bosco
4 · Forte
Sotto il limite
3 · Marcato
Apri la mappa completa

In sintesi

15-30cm of snow is expected Monday depending on location. Watch locally for snow amounts and slab development. We are also waiting to see how this new snow impacts the deeper weak layers as they are hard to predict. Rain is possible in lower elevation locations such as Kootenay Park.

Problemi valanghivi

  • Persistent Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Likely
    Dimensione
    1.5–2.5

    Three persistent weak layers formed in January are down 60-110 cm. Buried sun crusts on steep solar slopes present the greatest concern for triggering, however, weak facets and isolated surface hoar can be found on the same interfaces on shaded aspects. A few avalanches on these layers have been observed in the past week which could become more reactive with increased load.

  • Storm Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Likely - Very Likely
    Dimensione
    1–2

    New snow over the day Monday with wind will likely develop storm slabs in many areas. There is uncertainty as to how much snow will fall and where. Watch locally for development, and consider overhead exposure as the chance of natural avalanches may increase.

  • Deep Persistent Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Likely
    Dimensione
    1.5–3.5

    Weaker facets and depth hoar remain at the bottom of the snowpack and inspire little confidence. Depending on how much snow we get Monday and Tuesday, this layer may become more reactive. Be especially cautious in thin or rocky areas, where triggering is more likely. Cornice failures or smaller avalanches may act as a trigger for this layer so careful consideration of the slopes above your head is wise.

Confidence

Moderate

Avalanche Summary

No new avalanches have been reported or observed in the past 24 hours. There have been plenty of recent avalanches over the past few weeks, with many stepping to the ground. However, activity has tapered off in recent days with few weather inputs.

Snowpack Summary

A sun crust is present on steep solar slopes at treeline and below while 10-30 cm of soft snow can be found on northerly aspects. The various Jan PWL interfaces (sun crusts, facets, and surface hoar) are now down 40-80 cm. The weaker Nov. 16 basal facet layer is down 50-120 cm producing variable results in snowpack tests.

Weather Summary

10-30cm is expected Monday and Tuesday.

Monday: 5-10cm on West facing slopes, and 2-4 cm further East. Freezing levels, in general, will be 1500-1700m with potential rain below treeline. Winds will be S/SW 50-60 km/h and temperatures 0 to -5C at ridgetop. Snow continues Monday night with 5-10cm and potentially higher amounts in Kootenay with 20cm possible.

Tuesday: Tapering residual snow and winds through the day with the passage of a cold front.

For a more detailed forecast click here.

Terrain and Travel Advice

  • Uncertainty is best managed through conservative terrain choices at this time.
  • Avoid thin areas like rock outcroppings where you're most likely to trigger avalanches failing on deep weak layers.

Regioni coperte