Bollettino valanghe

Jasper

May 5 – 6, 2019Parks Canada
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Archiviato · scaduto 7 years ago

Pericolo valanghe

Tue
Wed
Alta quota
2 · Moderato
Limite del bosco
2 · Moderato
Sotto il limite
1 · Debole
Apri la mappa completa

In sintesi

As Spring finally re-asserts itself, expect to see increasing activity with daytime warming.  Meanwhile, incremental loading by small snowfalls has maintained winter-like avalanche problems on shaded slopes.

Problemi valanghivi

  • Wind Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Possible
    Dimensione
    1–2.5

    Wind slabs are more prevalent in the Marmot/Maligne areas than the icefields, as they received more recent snowfall and wind.

  • Persistent Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Unlikely - Possible
    Dimensione
    1.5–3

    Weak mid-pack facets, in isolated pockets on shaded, wind-sheltered alpine slopes. May also exist on shaded upper treeline features; and on solar aspects there is a (smaller) possibility of these failing on facets over a buried crust down 15-40cm.

  • Loose Wet

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Possible
    Dimensione
    1–1.5

    Springs' increasing influence is encouraging the upper snowpack to shed recent snowfall, in loose snow avalanches. Snowballing or sticky snow are indicators of this problem.

Weather Forecast

Mon-Weds: Mixed sun & cloud, light winds, no significant precip, gradually rising freezing level. Initially cool overnight temps become warm by midweek.

Mon: Scattered cloud, Freezing levels 2500m, treeline low -4, High +3

Tues: Cloud & flurries developing. Freezing level 2600m, treeline low -1.5, high +5

Wed: Treeline Low -0.5, freezing level 2700m.

Snowpack Summary

Regular small, warm snowfalls have sustained Windslab and loose snow avalanche problems. This recent snow is settling rapidly, but overlies crusts and facets in the upper snowpack. The crusts are thick/strong on solar aspects. Occasional whumpfing at upper treeline & alpine. The snowpack remains faceted on shady aspects, and weak in shallow areas.

Avalanche Summary

On Sunday, a large natural slab avalanche was observed at 2400m on a NE aspect. This was on Pyramid mountain near Jasper, and was most likely a recent Wind Slab (size 2.5). Numerous small (size 1), natural loose dry avalanches were also observed on steep shaded alpine terrain near Marmot Basin.

Confidence

Due to the number of field observations on Sunday

Regioni coperte