Bollettino valanghe

Jasper

Apr 14 – 15, 2017Parks Canada
Vedi sulla mappa
Archiviato · scaduto 9 years ago

Pericolo valanghe

Sun
Mon
Alta quota
3 · Marcato
Limite del bosco
2 · Moderato
Sotto il limite
1 · Debole

In sintesi

Plan your day to avoid slopes with overhead hazards such as cornices and/or windslabs.  The new snow and wind in the forecast will make these more sensitive and large loads can trigger the deep persistent slab that is widespread in the forecast area.

Problemi valanghivi

  • Wind Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Possible
    Dimensione
    1–3
    15 cm of new snow with moderate SW winds will create reactive alpine windslab on lee slopes.  If triggered, these could step down to the deep persistent slab resulting in very large avalanches.
  • Cornices

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Unlikely - Possible
    Dimensione
    2–3
    New snow and wind will increase the likelihood of cornice failure.
  • Deep Persistent Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Unlikely - Possible
    Dimensione
    2–4
    The deep instability could be triggered by large loads such as a cornice failure or a surface avalanche. Human triggering is most likely from shallow spots or on steep unsupported slopes.

Weather Forecast

15 cm of snow expected by Saturday evening with moderate SW winds. Freezing level peaking at 1700 m on Saturday.  Sun and warming temperatures coming on Sunday.

Snowpack Summary

New windslab on open slopes above 2400m. Dryer surface snow on polar aspects over a solid mid-pack bridging the weak base above 2000m. The base is a combination of weak facets and depth hoar mixed around a Nov rain crust. A consistent melt-freeze cycle is occurring below tree line.

Avalanche Summary

Several large windslab avalanches around 2400 m on x-loaded gulley features and steep lee slopes observed south of  Icefields on Friday.

Confidence

Timing, track, or intensity of incoming weather system is uncertain on Saturday

Regioni coperte