Bollettino valanghe

South Rockies

Apr 9 – 10, 2023Avalanche Canada
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Archiviato · scaduto 3 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

Prepare for a wet and stormy day. Avoid avalanche terrain during periods of heavy loading from rain, snow or wind.

Observe your local conditions, and let that guide your terrain choice. Forecasted snow and rainfall amounts are uncertain.

Problemi valanghivi

  • Storm Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Likely
    Dimensione
    1–3

    Storm slabs will be building through the day on Monday.

    Strong southwest winds at high elevations could be building deeper, more reactive pockets of slab in leeward terrain.

    Storm slabs in motion may step-down to deeper layers in the snowpack that may have been weakened by rising temperatures and/or rain.

    Use extra caution around ridgecrests, rolls, and on convex slopes. Retreat to mellower terrain if you find signs of instability like shooting cracks, whumpfs, or recent avalanches.

  • Loose Wet

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

    At treeline and below, the precipitation will fall as rain, and through the day, the upper snowpack is likely to become wet and unstable.

    If you see signs of a rapidly warming snowpack, like snow that feels like a slurpy, or clumps up and pinwheels down a slope, retreat to mellower terrain.

  • Deep Persistent Slabs

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

    The base of the snowpack remains weak. Avoid thin, rocky start zones and shallow areas with variable snowpack depths.

Confidence

Low

Avalanche Summary

No recent avalanches have been reported. Expect avalanche activity to increase on Monday with the arrival of a wet storm.

If you head out in the backcountry, let us know what you are seeing by submitting a report to the Mountain Information Network.

Snowpack Summary

10-15 cm of recent snow in the alpine covers settling, dry snow on shaded (northerly) aspects, and a frozen crust on solar aspects. At treeline, this new snow is likely to be denser, shallower, and moist.

Below treeline, 10-15 mm of rain starts to soak frozen crusts or already wet surfaces, and will be eating away at the snowpack at low elevations.

The mid snowpack is generally settled and strong, except in areas with snow depths less than 150 cm. In these lower snow areas, the mid-pack is likely weaker and more faceted.

The lower snowpack includes a layer of large, weak facets and/or depth hoar crystals.

Weather Summary

Snow/Rain amounts for the incoming storm are uncertain. Weather models are not agreeing on how widespread or intense the precipitation will be. Prepare to continually evaluate the conditions, and change plans as necessary.

Sunday Night

Cloudy. 5-10 cm of snow expected in the alpine, rain below 2000 m. Treeline temperature around 0 °C. Light to moderate southwest ridgetop wind, trending to strong at higher elevations.

Monday

Cloudy. 15-20 cm of snow expected in the alpine, rain below 2000 m. Possible isolated areas of 30mm or more. Treeline temperature around 0°C. Light to moderate southwest ridgetop wind, trending to strong at higher elevations.

Tuesday

Mostly Cloudy. Moderate to heavy rain overnight turning to snow as the snow/rain line drops to 1000 m. 5-10mm, possible isolated areas of 40 mm or more. Light southwest ridgetop wind trending to strong at higher elevations.

Wednesday

Mostly cloudy. 5-10 cm of snow expected. Treeline temperature around -5°C. Light variable ridgetop wind.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Storm slab size and sensitivity to triggering will likely increase through the day.
  • Be careful to keep storm day fever from luring you out into bigger terrain features.
  • A moist or wet snow surface, pinwheeling and natural avalanches are all indicators of a weakening snowpack.
  • Avoid thin areas like rock outcroppings where you're most likely to trigger avalanches failing on deep weak layers.

Regioni coperte