Bollettino valanghe

Jasper

Apr 20 – 21, 2018Parks Canada
Vedi sulla mappa
Archiviato · scaduto 8 years ago

Pericolo valanghe

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

In sintesi

Avoid all slope with cornices overhead as there is recent evidence of them falling recently. This is considered a large trigger on the slope below.

Problemi valanghivi

  • Wind Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Possible
    Dimensione
    1–2
    Although mostly thin some wind slabs are up to 40cm thick in alpine terrain. Solar radiation and cornice collapses can trigger these events. Once triggered the potential to trigger deeper weaknesses exists resulting in larger avalanches.

  • Persistent Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Possible
    Dimensione
    2–3.5
    These events require a significant force to trigger them such as a large cornice failure or avalanche debris from above. Once triggered they can be very large and run far into the valley below. Many slopes have already been triggered.

  • Loose Wet

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Possible
    Dimensione
    1–2
    Pay close attention to the effect of solar radiation and daytime warming. Point release from rocks and cliff terrain can trigger isothermal snow below. This will be of most concern in the late afternoon.

Weather Forecast

Saturday will be cloudy, sun and flurries, 5cm of snow, -2 C, West winds 25-50km/hr, and freezing level 1900m. Sunday will be a mix of sun and cloud, -10 to -5, West winds 15-45km/hr, and freezing level 1600m. Monday will be sun and cloud, no precipitation,  -9 to plus 1 C, light winds, and 2400m freezing level.

Snowpack Summary

Windslabs are up to 40cm deep. Sun or temperature crusts extend to treeline and continued into the alpine on southerly slopes. Persistent slabs can be found on most aspects at treeline and above. These have been most reactive recently to large triggers like cornice failures. Below 1,900m the snowpack is isothermal.

Avalanche Summary

No patrol Friday. In the past 48hrs persistent slab avalanches up to size 3.5 have occurred from alpine terrain. They are size 2-2.5 and are are being triggered by cornice failures or small windslab avalanches stepping down to these deeper layers. With freezing levels reaching treeline expect some loose avalanches on South to West facing slopes.

Confidence

Freezing levels are uncertain

Regioni coperte