Bollettino valanghe

Purcells

Feb 16, 2019Avalanche Canada
Vedi sulla mappa
Archiviato · scaduto 8 years ago

Pericolo valanghe

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

In sintesi

It is possible the south of the region could see more snow than forecast. If amounts exceed 15 cm, consider this region considerable.

Problemi valanghivi

  • Wind Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Possible - Likely
    Dimensione
    1–2
    Recent strong winds from the northeast have set up wind slabs on unusual southerly and westerly aspects. Previous old wind slabs on other aspects are likely reactive too.

  • Persistent Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Unlikely - Possible
    Dimensione
    1.5–2.5
    Two weak layers of surface hoar crystals are buried between 30 and 60 cm in the snowpack. The layers are most prominent around treeline and below treeline elevations.

Confidence

Moderate - Forecast snowfall amounts are uncertain on Saturday

Weather Forecast

FRIDAY NIGHT: 5-10 cm of low density snow expected, with more likely in southern areas. Mostly light winds.SATURDAY: Around 5 cm new snow. Treeline temperatures around -8C. Light northeasterly winds.SUNDAY: Dry and cloudy. Treeline temperatures around -11C. Light northeasterly winds.MONDAY: Dry, with some clear spells. Treeline temperatures around -12C. Moderate northwesterly winds.

Avalanche Summary

Reports on Tuesday, Wednesday and Thursday include a few wind slab avalanches size 1-2 on north, south and east aspects in the alpine. There were also a few storm slab avalanches reported to size 1 at treeline. Additionally on Wednesday there was a cornice triggered size 3 deep persistent slab reported on a northeast aspect at 2800m.

Snowpack Summary

10-20 cm recent low density snow has been blown around by strong northeasterly winds, creating touchy wind slabs in exposed areas. This new snow sits above wind-affected snow and/or sugary facets. In the far south of the region (south of Cranbrook) recent storm amounts are more like 30-40 cm of new snow. Beneath this lies two weak layers of surface hoar that were buried at the end of January and mid-January. These layers are around 30 to 60 cm deep. The deeper (mid-January) layer may be associated with a melt-freeze crust on southerly aspects. These layers are most prominent at treeline and below treeline elevations.The base of the snowpack is composed of weak and sugary faceted grains that overly a melt-freeze crust. This weak layer has produced large and destructive avalanches that are sporadic in nature and very difficult to predict. It is most likely to be triggered from areas where the snowpack is shallow and weak. Rocky alpine bowls, ridge crests, and rocky outcroppings are some examples of terrain features to be wary of. See the Forecaster Blog here for more info on this problem.

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