Bollettino valanghe

Cariboos

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

Pericolo valanghe

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

In sintesi

Easterly winds formed wind slabs on lee aspects in the alpine.

Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.

Problemi valanghivi

  • Wind Slabs

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

    Easterly winds have formed wind slabs on lee aspects in the alpine.

  • Deep Persistent Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Unlikely
    Dimensione
    2.5–4

    A weak layer of facets exists near the base of the snowpack. The likelihood of human triggering is low given the layer's depth, but large triggers such as cornice failures or smaller avalanches in motion have the potential to produce very large avalanches with surprisingly wide propagation. Suspect terrain for human triggering includes steep, shallow, and rocky terrain where the snowpack transitions from thin to thick.

Confidence

High

Avalanche Summary

One rider triggered size 1.5 wind slab on a west aspect in the alpine was reported on Friday.

Snowpack Summary

Easterly wind has formed small wind slabs on lee aspects at treeline and above. Sun crust on sunny slopes and surface hoar (3-10 mm) on shady slopes at all elevations. Previous wind effect in open areas at treeline and above.

The mid-snowpack is generally strong but the lower snowpack is a different story. The November facets are still prominent at the base of the snowpack. They are showing signs of rounding but there is still a considerable step in resistance between them and the overlying snow. These facets are most pronounced in shallow rocky areas.

Weather Summary

Saturday Night

Partly cloudy with isolated flurries; 0-5 cm / Light south ridgetop wind / Low temperature at treeline around -12 C / Freezing level valley bottom.

Sunday

Mix of sun and cloud / Light south ridgetop wind / High temperature at treeline around -3 C / Freezing level 800 m.

Monday

Snow; 10-20 cm / Strong southwest ridgetop wind / High temperature at treeline around 0 C / Freezing level 1300 m.

Tuesday

Mix of sun and cloud with isolated flurries; 3-5 cm / Light southwest ridgetop wind / High temperature at treeline around -4 C / Freezing level 1000 m.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
  • Use extra caution around cornices: they are large, fragile, and can trigger slabs on slopes below.
  • Avoid shallow, rocky areas where the snowpack transitions from thick to thin.
  • Avalanche hazard may have improved, but be mindful that deep instabilities are still present.

Regioni coperte