Bollettino valanghe

Waterton Lakes

Feb 20 – 23, 2015Parks Canada
Vedi sulla mappa
Archiviato · scaduto 12 years ago

Pericolo valanghe

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

In sintesi

While travel at lower elevation remains difficult with poor coverage, it is still winter above 2000m and new, as well as old slabs remain available for human triggering. Cooler temperatures and a bit more snow should help freshen things up.

Problemi valanghivi

  • Wind Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Possible
    Dimensione
    1–2
    Moderate ridge top winds mainly from the West have developed thin new slabs at treeline and above these will continue to develop with the addition of new snow on Friday.

  • Persistent Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Unlikely - Possible
    Dimensione
    1–2
    These old windslabs continue to  produce reluctant shears 25 to 50 cm deep in the upper snowpack and are a concern above 2200m. Keep an eye on these if you are considering taking on serious terrain.

  • Deep Persistent Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Unlikely - Possible
    Dimensione
    2–3
    Now 40 to 120cm deep these slabs continue to stand out as a concern in the TL and ALP areas where there is not a strong Jan 31 crust over them (2200m+). Be particularly mindful in thin snowpack areas where this layer is more likely to be triggered.

Weather Forecast

The Northerly flow is bringing cooler conditions for the weekend. Skies will become overcast late Thursday night and a welcome pulse of snow should arrive midday Friday from the prairies. By noon Saturday expect clearing and dropping temperatures as a NE flow continues to bring Arctic air into the mountains.

Snowpack Summary

Thin new windslabs now sit on the Feb 14 temperature crust that exists to 2300m and thin solar crusts to mountain top. Below this old windslabs cap the 50 to 80 cm slab that seems well bonded to the Jan 31 crust. The Mid-December layer that is down over 1m  in most deep areas remains a concern in high shaded terrain presenting a shallow snowpack.

Avalanche Summary

Conditions have remained relatively cool with good overnight freezes. The February 14 crust has not been heated to the point of breaking down and is effectively limiting avalanche problems to minor surface concerns below 2000m and to ridge top on solar aspects.  Elsewhere, concern for human triggering remains.

Confidence

Regioni coperte