Bollettino valanghe

West Slopes North

Northwest Avalanche Center
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Pericolo valanghe

Sun
Alta quota
3 · Marcato
Limite del bosco
3 · Marcato
Sotto il limite
2 · Moderato
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In sintesi

It’s exciting to see a storm lining up for Valentine’s Day weekend, but this isn’t a typical midwinter cycle. Weak layers may exist on and near the old snow surface, and new loading could produce large avalanches that are easier to trigger and wider than expected. Avoid steep slopes, especially if you notice shooting cracks, whumphing, or recent avalanche activity.

Problemi valanghivi

  • Storm Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Likely
    Dimensione
    1–2

    Large, dangerous avalanches could catch you off guard on Saturday. Choose sheltered, lower-angle terrain and avoid steep slopes where more than about 6 inches of new snow has accumulated. Where storm totals approach a foot or more — and especially in wind-loaded areas — a person could trigger a large, potentially fatal avalanche.

    Shady slopes may be more reactive if weak layers linger in or on the old snow surface, but we don’t yet know how widespread this problem is. Getting away with one slope doesn’t mean the next is safe — this isn’t a day to test your luck.

    Avoid high-consequence terrain: steep slopes connected to gullies, cliffs, trees, or rock fields that could amplify the effects of getting caught in an avalanche. 

    Example photo: With a human trigger, it's likely that you can trigger a large avalanche like this one for Valentine's Day. Don't wreck your and your partner's date day by getting caught in an avalanche. 

Avalanche Discussion

Even if you’ve been waiting all season for soft snow and steep lines, Saturday isn’t the day to commit to big terrain. A buried weak layer may exist, but this is the first significant load on it, and we don’t yet know if roughly a foot of snow — or less in some areas — is enough to make the snowpack reactive. We also don’t know how widespread the weak snow is. Instead of a heavy storm like 2 ft of wet snow with clear failures that wipe out our concerns, we’re in a gray zone where behavior will be uncertain.

Small, dry, loose avalanches are possible in the new low-density snow. There may be a few afternoon sun breaks, further initiating any loose avalanches. The old snow layer, especially if hard at the surface like on south-facing slopes, could provide a good sliding surface in an avalanche. Beware of hard, bumpy features beneath the new snow layer. 

Snowfall totals will vary widely for this storm. The Baker backcountry may see storm totals around a foot by Saturday morning, while areas farther east may receive about half that amount and have lower danger. Some lower elevations may hold 6 inches or more. Near the top of the lower elevation band, there may be smooth, continuous old snow layers that avalanches could run on, especially on shady aspects, whereas south-facing slopes and lower elevations may just have a fresh coating of snow over the ground with minimal avalanche concern. 

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