Bulletin d’avalanche

Selkirk Mountains

Idaho Panhandle Avalanche Center
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Danger d’avalanche

Sun
Alpin
3 · Marqué
Limite forestière
2 · Modéré
Sous la limite
2 · Modéré
Périmé — ce bulletin a expiré last year. Vous consultez des conditions passées, pas le bulletin en cours.

Points saillants

Several days of above-freezing temperatures—combined with sunshine, rain, and meltwater—have weakened the snowpack, creating a complex mix of wet snow hazards. With cooler temperatures now returning, uncertainty remains about how quickly the snowpack will stabilize and refreeze. Maintain a cautious approach and avoid steep slopes with a wet, punchy surface as we transition to a cooler weather pattern. At higher elevations, be mindful of small, isolated new snow hazards as 2-6 inches of snow fell above 5500 feet.

Problèmes avalancheux

  • Wind Slabs

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

    Elevations above 5,000 feet received 2–6 inches of snow yesterday, accompanied by light to moderate southwest winds. As a result, fresh wind slabs have likely formed on northerly-facing slopes but also on east and southeast-facing slopes. These fresh drifts, which may be a couple of feet thick, have been deposited on a frozen surface, making them particularly prone to avalanching.

    Be especially cautious near ridgelines on the leeward side, where wind slabs are most likely to have accumulated. Signs of newly formed wind slabs include cracking, wind etching, and pillow-shaped drifts. These slabs will likely be easy to trigger and could be large enough to knock you down or bury you. It's best to avoid areas with fresh wind loading and choose alternative travel routes.

    (3/28/2025)

    Ski pressure on steeper slopes easily sheeted the new snow above the old, refrozen but breakable crusts. These were fairly predicatable and easy to manage, but traveled quick down the slope. Selkirk Mountains. March 28, 2025.

    Photo: Chris Bilbrey

  • Wet Slabs

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Possible
    Taille
    2–3

    Mountain temperatures have remained at or above freezing for an extended period, accompanied by significant rainfall, meltwater, and intermittent sunshine. Before this warm-up, early March saw an increase of 3–5 feet of lower-density snow. Since the onset of warm and wet conditions about a week ago, rain and meltwater have saturated the snowpack, including pre-existing weak layers. As a result, the snowpack has settled by 10–20 inches over the past week. Currently, the upper 2 feet of the snowpack remains wet and non-cohesive. However, cooler temperatures yesterday, along with a couple of inches of snow at higher elevations, have made the upper 6–8 inches more supportable.

    While snowpack stability is gradually improving, natural or human-triggered wet slab avalanches remain possible. These avalanches could step down, triggering larger avalanches. This risk is most pronounced near the treeline, where wet snow problems are most likely to intersect due to the significant amount of free water moving through the snowpack.

    (3/26/2025) Photo: Idaho Panhandle Avalanche Center

  • Loose Wet

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

    Mountain temperatures have remained at or above freezing for an extended period, accompanied by significant rainfall, meltwater, and intermittent sunshine. Before this warm-up, early March saw an increase of 3–5 feet of lower-density snow. Since the onset of warm and wet conditions about a week ago, rain and meltwater have saturated the snowpack, including pre-existing weak layers. As a result, the snowpack has settled by 10–20 inches over the past week. Currently, the upper 2 feet of the snowpack remains wet and non-cohesive. However, cooler temperatures yesterday, along with a couple of inches of snow at higher elevations, have made the upper 6–8 inches more supportable.

    While snowpack stability is gradually improving, natural or human-triggered wet loose remain possible especially at lower elevations or on solar aspects. These avalanches and pinwheeling snow are good indicators of a week snowpack which could step down, triggering larger wet slab avalanches. Be especially aware of wet loose avalanches if the sun pokes out today.

    Photo: Mikey Church

Avalanche Discussion

Although today is cooler than yesterday, much of the region has remained above freezing for multiple days. While today's dryer skies and slight temperature drop will help stabilize some surface instabilities, it won’t be enough to fully lock up the snowpack or significantly reduce the risk of large to very large wet slab avalanches. If the sun peeks out today surface melting and warming could increase quickly on solar aspects.

In recent days, numerous wet slab avalanches have been observed, breaking on distinct layers within the upper snowpack, including crusts from 3/9 and 3/19 buried 1 to 3 feet below the surface. The Sunday/Monday rain event, which primarily impacted northern zones, and midweek meltwater from unseasonably warm temperatures have introduced abundant liquid water into the snowpack, further lubricating weak layer interfaces. While the peak of natural avalanche instability has likely passed, a skier or rider could still trigger a dangerous large to very large avalanche in steep terrain today. Wet loose avalanches are less of a concern, but if you see snow starting to entrain, take it as a warning to move to safer, less exposed terrain.

With cooler temperatures returning and overnight lows expected to drop below freezing in the coming days, the upper snowpack will gradually strengthen, helping to cap instabilities buried deeper within. However, for now, patience is key—waiting for more stable and predictable spring conditions is the safest approach before committing to steeper and more complex objectives.

Régions couvertes