Bollettino valanghe

Jasper

Apr 5 – 6, 2017Parks Canada
Vedi sulla mappa
Archiviato · scaduto 9 years ago

Pericolo valanghe

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

In sintesi

Cautious route-finding and conservative decisions is critical  the next few days. Thursday to Friday's precipitation will be rain at lower elevations raising the potential for loose wet avalanches below  treeline locations.   

Problemi valanghivi

  • Wind Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Possible
    Dimensione
    1–3
    Expect wind-slab formation by current strong SW winds particularly off alpine ridges and cross-loaded gullies. If triggered, could step down to the deep persistent slab.

  • Cornices

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Possible
    Dimensione
    2–3
    Cornice failure is hard to predict but is more likely with inputs like solar radiation and wind-loading. Some very large cornices out there.

  • Deep Persistent Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Possible
    Dimensione
    2–4
    This problem is unlikely to disappear. It can be triggered by large loads like cornice fall or wind-slab avalanche. Human triggering is most likely from shallow spots or on steep unsupported slopes.

Weather Forecast

Thursday to Friday freezing level may be 2200m, rain in valley bottom with possibly 15cm of snow in higher elevations by Friday afternoon. Winds may shift Easterly on Friday afternoon with a second pulse of precipitation. Possibly a slight cooling trend on Saturday.

Snowpack Summary

Good skiing between 1900-2400m in sheltered areas. Wind-slab along lee ridge-lines and cross-loaded gully features from strong SW winds. Mid-pack bridging basal weakness. Lower snowpack is weak with a combination of facets, Nov rain crust and depth hoar. Below tree line a supportive 20cm melt freeze crust sits above a weak facet layer to ground.

Avalanche Summary

Helicopter flight from Jasper to Sunwapta Resort to Maligne. No new avalanches noted on this flight and visibility was good but very windy at ridge-tops. Tuesday's Bald Hill patrol also did not note any new avalanches. Previous cornice and wind-slab failures have triggered the deep persistent slab resulting large full path avalanches.

Confidence

Freezing levels are uncertain

Regioni coperte