Bollettino valanghe

South Rockies

Mar 30 – 31, 2023Avalanche Canada
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Archiviato · scaduto 4 years ago

Pericolo valanghe

Sat
Sun
Alta quota
2 · Moderato
Limite del bosco
2 · Moderato
Sotto il limite
1 · Debole
Apri la mappa completa

In sintesi

A weak snowpack still exists throughout this region.

Avoid thin and rocky start zones.

Problemi valanghivi

  • Deep Persistent Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Unlikely - Possible
    Dimensione
    2–4

    The base of the snowpack remains very weak. Very large human-triggered avalanches are possible at treeline and above. Avoid thin, rocky start zones and shallow areas with variable snowpack depths. Weak layers are most triggerable here as they sit closer to the surface of the snowpack.

    Give careful consideration to the slopes overhead as large avalanches may run well into the runout zone or into lower-angle terrain.

    Deep persistent avalanches are challenging to predict. This layer can suddenly become active again, typically when there is rapid change or stress to the snowpack - sudden warming, heavy snow or rainfall, or heavy loads eg. cornice fall.

Avalanche Summary

Wet loose avalanches have occurred over the last 3 days, on steep sun affected slopes as freezing levels rose with strong sunshine.

No activity on the deeply buried weak layers has been reported this week. Kananaskis Country and the central Rockies continue to report very large deep persistent avalanches, including a size 3 natural on the 28th of March in Highwood Pass. Thin and rocky terrain features in the upper treeline and alpine should still be avoided.

Confidence

Moderate

Snowpack Summary

Moist snow exists on the surface at most elevations. At high elevations on shaded slopes, dry snow may still exist. Below this, a crust exists on solar aspects, and faceted snow and surface hoar up in shaded and wind-sheltered areas.

In the middle of the snowpack, there are lingering persistent weak layers, including surface hoar in wind-sheltered terrain and a sun crust on south aspects. These layers have not shown recent reactivity, but may still be triggerable in isolated areas and should be on your radar, particularly in the Purcells part of the region.

The lower snowpack is made up of a widespread layer of large, weak basal facets and depth hoar in some areas, which produced large avalanches in the Elk Valley and the neighboring region of Purcells last week. Kananaskis Country reports continued avalanche activity on this layer.

Weather Summary

Thursday Night

Freezing levels drop back to 500 m, with light westerly winds around 10 km/hr. Partly cloudy skies.

Friday

Mostly cloudy with flurries delivering up to 5 cm of snow. Light southerly wind gusting 40 km/h. Freezing level rises to 1500 m. Alpine temperatures of -5 °C.

Saturday

Cloudy with sunny periods possible in the afternoon. Light snowfall brings 5-10 cm. Light southwesterly wind gusting 40 km/h. Freezing level rises to 1500 m. Alpine temperatures of -5 °C.

Sunday

Cloudy with up to 5 cm of snow. Light southwest winds. Freezing levels around 1300 m, alpine highs of -7 °C.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Avoid thin areas like rock outcroppings where you're most likely to trigger avalanches failing on deep weak layers.
  • Conditions may have improved, but be mindful that deep instabilities are still present.
  • Pay attention to cornices and give them a wide berth when traveling on or below ridges.

Regioni coperte