Lawinenlagebericht

North Columbia

Apr 19 – 20, 2023Avalanche Canada
Auf der Karte ansehen
Archiviert · abgelaufen 3 years ago

Lawinengefahr

Fri
Sat
Hochgebirge
2 · Mässig
Waldgrenze
2 · Mässig
Unterhalb
1 · Gering

Kernpunkte

Riders must manage various avalanche concerns that vary by elevation and aspect. Observe your local conditions and let that inform your terrain choices.

Lawinenprobleme

  • Persistent Slabs

    • Hochgebirge
    • Waldgrenze
    • Unterhalb der Waldgrenze
    Wahrscheinlichkeit
    Unlikely - Possible
    Größe
    1.5–2.5

    A layer buried on April 1, down roughly 50 to 100 cm from the surface, appears to be most reactive on solar tilted slopes where surface hoar may sit on a hard melt-freeze crust.

  • Storm Slabs

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

    Scattered flurries continue to build storm slabs and may need time to bond to underlying surfaces. Be especially cautious at higher elevations, near ridges and mountain tops were wind has likely increased slab depth and reactivity.

  • Deep Persistent Slabs

    • Hochgebirge
    • Waldgrenze
    • Unterhalb der Waldgrenze
    Wahrscheinlichkeit
    Unlikely
    Größe
    2.5–4

    A weak layer of facets exists near the base of the snowpack. The likelihood of human triggering is low given the layer's depth.

    Suspect terrain includes steep, shallow, and rocky terrain where the snowpack varies between thin and thick.

Confidence

Moderate

Avalanche Summary

A number of persistent slab avalanches were reported on Tuesday, up to size 2. They were a combination of explosive and skier triggered, and all appear to have failed on a recently buried (April 1) surface hoar/crust combination. All reported avalanches occurred in the western Purcells.

In the Selkirks the avalanche activity appears to be slowing. However, many natural and human-triggered avalanches were reported last week. Many of these are sliding on recently buried melt-freeze crusts, including a fatal avalanche in the western Purcells and a close call near Revelstoke.

Snowpack Summary

Dry, powder snow remains at higher elevations on north-facing terrain. While multiple melt-freeze crusts or moist snow are likely to be found on steep solar slopes and at lower elevations.

A layer of surface hoar persists down roughly 50 to 100 cm from the surface and appears to be variable in its distribution. The surface hoar may be sitting on top of a thin melt-freeze crust on all but true north-facing slopes. Despite a decrease in avalanche activity on this layer, avalanche professionals continue to closely monitor it.

The mid-snowpack is strong. However, the November depth hoar remains at the base of the snowpack and remains a concern in rocky, shallow, variable depth snowpack areas at treeline and above.

Weather Summary

Wednesday night

Cloudy with clear periods. Light west ridgetop winds. Treeline temperature 0 to -5 C.

Thursday

Cloudy with sunny periods. Light south ridgetop winds. Treeline temperatures 0 to -5 C. Freezing level 1800 m.

Friday

Mix of sun and cloud. Light south ridgetop winds. Treeline temperatures 0 to -5 C. Freezing level 1700 m.

Saturday

Mostly cloudy with scattered flurries. Light south ridgetop winds. Treeline temperatures 0 to -5 C. Freezing level 1700 m.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Closely monitor how the new snow is bonding to the crust.
  • Be alert to conditions that change with elevation and sun exposure.
  • If you are increasing your exposure to avalanche terrain, do it gradually as you gather information.

Abgedeckte Regionen