Bulletin d’avalanche

Flathead

Feb 28 – Mar 1, 2026Avalanche Canada
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Archivé · expiré 7 months ago

Danger d’avalanche

Mon
Tue
Alpin
3 · Marqué
Limite forestière
3 · Marqué
Sous la limite
3 · Marqué
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Points saillants

It's a challenging snowpack.

Strong winds have left slabs in open features, while persistent slab avalanches are most likely in sheltered areas at treeline and below.

Problèmes avalancheux

  • Wind Slabs

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Possible
    Taille
    1–2

    Recent wind slab formation has been extensive, and stubborn slabs could extend into openings below treeline.

  • Persistent Slabs

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Possible - Likely
    Taille
    1.5–3

    Be aware of the potential for remote triggering and large avalanches due to buried surface hoar, especially at treeline and below.

Confidence

Moderate

  • We are uncertain about how quickly persistent slabs are gaining strength.

Avalanche Summary

On Thursday, riders triggered a size 1.5 persistent slab on a steep slope from a treed ridge; the crown was 50 cm thick.

On Tuesday, natural and explosive-triggered wind slab avalanches to size 2 were reported on north and east alpine aspects.

Last weekend, numerous persistent slab avalanches up to size 3 were reported on all aspects and elevations. They were triggered accidentally, naturally, and remotely.

See recent MIN reports here and here for further details.

Snowpack Summary

20 cm of recent snow and variable strong winds have formed wind slabs on a variety of aspects and elevations, including open areas below treeline.

In the top 125 cm of the snowpack, there are multiple concerning weak layers of surface hoar and/or crusts/facets. The majority of recent persistent slab avalanches have been on well-preserved surface hoar in sheltered areas at treeline and below.

The mid and lower snowpack are well settled.

Weather Summary

Friday Night

Mostly cloudy. 1 to 5 cm of snow. 50 km/h west ridgetop wind. Treeline temperature -5 °C.

Saturday

Mostly sunny. 40 km/h west ridgetop wind. Treeline temperature -6 °C.

Sunday

Sunny. 40 km/h west ridgetop wind. Treeline temperature -4 °C.

Monday

Sunny. 40 km/h west ridgetop wind. Treeline temperature -2 °C.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Watch for signs of instability like whumpfing, hollow sounds, shooting cracks, or recent avalanches.
  • Keep your guard up at all elevations. Wind slab formation has been extensive and could extend into openings below treeline.
  • Be aware of the potential for remote triggering and large avalanches due to buried surface hoar.
  • In times of uncertainty, conservative terrain choices are our best defense.

Régions couvertes