Bollettino valanghe

South Rockies

Apr 11 – 12, 2023Avalanche Canada
Vedi sulla mappa
Archiviato · scaduto 3 years ago

Pericolo valanghe

Thu
Fri
Alta quota
3 · Marcato
Limite del bosco
2 · Moderato
Sotto il limite
2 · Moderato
Apri la mappa completa

In sintesi

Expect rapidly changing daytime conditions as rising freezing levels, sunshine and potential intense bursts of snowfall are likely to elevate the danger levels.

Observe your local conditions, and let that guide your terrain choice.

Problemi valanghivi

  • Storm Slabs

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

    Storm totals have been recorded as between 20-40 cm and 25 mm of rain.

    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
    Likely
    Dimensione
    1–2

    During periods of daytime warming and sunshine, expect on steep south facing terrain the upper snowpack to unconsolidated rapidly.

    If you see signs of loose wet instability, like snow that feels like a slurpy, or clumps up and pinwheels down a slope, choose terrain with more shade and increased consolidation of the upper snowpack.

  • 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

Moderate

Avalanche Summary

No recent avalanches have been reported. It is likely that a widespread avalanche cycle occurred during the warm and wet storm. Natural and human triggered avalanches will remain likely during daytime periods of warming.

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

20-30 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 recent snow is likely to be denser, shallower, and moist or refrozen.

Below treeline, rain soaked surfaces are starting to freeze or get snowed on as temperatures drop, and a lot more dirt is showing 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

In the wake of the past warm storm front, unsettled weather will persist. This unsettled weather will bring brief but intense periods of snowfall and pinpointing the location of these localized events creates a high level of uncertainty with this weather forecast. Prepare to continually evaluate the conditions, and change plans as necessary.

Tuesday Night

Cloudy. 1 to 10 cm of snow. Freezing level descending to 600m, Alpine temperature low of -8°C. Light to moderate southwest ridgetop wind.

Wednesday

Cloudy with afternoon clearing. 1 to 10 cm of snow. Freezing level rises mid day to 1500m, Alpine temperature low of -1°C. Light south west backing to north west ridgetop wind.

Thursday

Cloudy with afternoon clearing. 1 to 10 cm of snow. Freezing level rises mid day to 1650m, Alpine temperature low of 0°C. Light north west ridgetop wind.

Friday

Cloudy with afternoon clearing. 1 to 5 cm of snow. Freezing level rises mid day to 1650m, Alpine temperature low of 0°C. Light north west ridgetop wind.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Continue to make conservative terrain choices while the storm snow settles and stabilizes.
  • Be alert to conditions that change with aspect and elevation.
  • Be alert to conditions that change throughout the day.
  • Watch for unstable snow on specific terrain features, especially when the snow is moist or wet.
  • Avoid thin areas like rock outcroppings where you're most likely to trigger avalanches failing on deep weak layers.

Regioni coperte