Lawinenlagebericht

Banff Yoho Kootenay

Mar 30 – 31, 2025Avalanche Canada
Auf der Karte ansehen
Archiviert · abgelaufen 2 years ago

Lawinengefahr

Tue
Wed
Hochgebirge
3 · Erheblich
Waldgrenze
3 · Erheblich
Unterhalb
2 · Mässig

Kernpunkte

Natural activity is tapering off, but uncertainty remains high. Approach terrain decisions with intention and allow for a margin of error.

Avalanche control is being conducted on Mt Stephen on Mar 31, 2025. This area will be closed.

Lawinenprobleme

  • Persistent Slabs

    • Hochgebirge
    • Waldgrenze
    • Unterhalb der Waldgrenze
    Wahrscheinlichkeit
    Possible - Likely
    Größe
    1.5–3.5

    A 60-100+ cm slab of dense snow now sits atop the persistent mid-pack facet layer from Jan/Feb. In thin snowpack areas weak depth hoar extends to the ground. There has been a lot of large avalanche activity on this facet layer, and where it hasn't avalanched, triggering it remains a major concern.

  • Storm Slabs

    • Hochgebirge
    • Waldgrenze
    • Unterhalb der Waldgrenze
    Wahrscheinlichkeit
    Possible - Likely
    Größe
    1–2

    Up to 30cm of settled of storm snow buries previous crusts and winds slabs. The new snow could fail as a storm slab in steep terrain, and has potential to step down to deeper weak layers in the snowpack. Any significant solar inputs on Monday will increase the likelihood of these slabs being triggered.

  • Loose Wet

    • Hochgebirge
    • Waldgrenze
    • Unterhalb der Waldgrenze
    Wahrscheinlichkeit
    Possible
    Größe
    1–2

    This problem is driven by air temperature and solar input. The latest storm snow sits on a crust and could slide easily if conditions warm, especially under strong sun. Heat and solar input remain uncertain in the models, so monitor conditions closely at the local level on Monday.

Confidence

Moderate

Avalanche Summary

The Parks Canada field team was up 93N today. Evidence of the recent avalanche cycle remain, but all observed slides are 24 hours old or older. Sunshine patrol reported a natural loose wet cycle to size 2. These slides were storm snow running on a crust. This is something to watch out for on Monday if the sun comes out.

Snowpack Summary

30cm of settled of storm snow over the past 3 days with the most in the Banff/Kootenay areas of the region. This new snow overlies rain and temperature crusts up to ~2500 m. A 50-100+ cm dense slab now sits over a persistent weak layer of facets from Jan/Feb. In Eastern areas with a thinner snowpack, these weak facets and depth hoar extend to the ground. In thicker snowpack regions west of the divide, the facet layer is not as pronounced and the lower snowpack is more settled.

Weather Summary

Light southerly winds will persist through Monday. Temperatures will remain seasonal or slightly cooler, with valley highs just above zero in the afternoon and ridge temperatures near -9°C. A minor system is expected to bring less than 5 cm of precipitation late Monday into early Tuesday.

Terrain and Travel Advice

  • Uncertainty is best managed through conservative terrain choices.
  • Be mindful that deep instabilities are still present and have produced recent large avalanches.
  • Give the new snow several days to settle and stabilize before pushing into bigger terrain.

Abgedeckte Regionen