Bollettino valanghe

Purcells

Mar 21 – 22, 2019Avalanche Canada
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Archiviato · scaduto 8 years ago

Pericolo valanghe

Sat
Sun
Alta quota
4 · Forte
Limite del bosco
4 · Forte
Sotto il limite
4 · Forte
Apri la mappa completa

In sintesi

The hot and sunny weather persists on Friday, which will likely continue the avalanche cycle on sunny slopes. The danger will be the highest when the day heats up, so make sure you are out of avalanche terrain early and with no overhead exposure.

Problemi valanghivi

  • Persistent Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Possible - Likely
    Dimensione
    1.5–3
    As the warming continues, the likelihood of triggering deeper weak layers rises. Best to avoid avalanche terrain during the heat of the day.

  • Loose Wet

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Very Likely
    Dimensione
    1–2.5
    The upper snowpack is destabilizing in the day with hot and sunny weather, producing large avalanches. The most problematic time is with maximum warming during afternoon hours. Best to avoid avalanche terrain on or beneath southerly aspects.

Weather Forecast

THURSDAY NIGHT: Clear skies, light southwest wind, alpine temperature 4 C, freezing level 3000 m.FRIDAY: Clear skies, light southeast wind, alpine temperature 4 C, freezing level 3000 m.SATURDAY: Cloudy with light snow in the high alpine and rain below, accumulation 1 to 3 cm, light southwest wind, alpine temperature 0 C, freezing level 2200 m.SUNDAY: Cloudy with snowfall, accumulation 5 to 10 cm, light southeast wind, alpine temperature -3 C, freezing level 1700 m.

Avalanche Summary

Many wet loose avalanches were observed between Sunday and Wednesday. They were large (up to size 3), occurred mostly on southeast to southwest aspects, and at all elevations. A notable persistent deep slab avalanche was also triggered on Wednesday, likely from a cornice fall. It was 100 cm deep on a northeast aspect at 2900 m.This avalanche cycle is expected to continue on Friday, as temperatures remain exceptionally warm and the sun shines strong. The cycle may end on Saturday, as freezing levels drop and cloudy skies prevail.

Confidence

High -

Snowpack Summary

The warm air and sunny skies have produced wet snow to ridge top on southerly aspects and up to around 2100 m on northerly aspects. The upper 20 to 30 cm of snow may slide easily during the day, either as loose wet snow or as a cohesive slab, as it sits over weak faceted grains or a melt-freeze crust. The wet snow may freeze into a melt-freeze crust overnight.A weak layer of faceted grains and/or feathery surface hoar crystals buried in mid-January may be found around 50 to 90 cm deep. Although this layer has been dormant for a few weeks, the current warm conditions may awaken this layer. Steep cutblocks and large open glades at lower elevations are the most likely places to trigger this layer.The base of the snowpack is composed of weak faceted snow, which may be associated with a melt-freeze crust. The warm air and sunny skies has increased the likelihood of triggering very large avalanches on this layer.

Regioni coperte