Avalanche forecast

West Slopes North

Northwest Avalanche Center
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Avalanche danger

Thu
Alpine
3 · Considerable
Treeline
3 · Considerable
Below
2 · Moderate
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Out of date — this forecast expired 6 years ago. You’re viewing past conditions, not the current bulletin.

Highlights

The snowpack needs time to adjust to the recent heavy loading event. Minimize exposure to large open slopes above, and seek out terrain less than 35 degrees. Be especially cautious around wind-loaded slopes at upper elevations. The sunshine may affect stability, and be careful not to let it compromise your decision-making.

Avalanche problems

  • Wind Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Likely
    Size
    2–3

    The West North Zone received 2-3ft+ of snow since Friday, and strong south and west winds blew over the past 48hrs. The most dangerous avalanche conditions continue to exist in wind-loaded upper elevation terrain where the potential for very large avalanches lingers. Natural avalanches even remain possible. Cornices have grown recently and could drop onto slopes below, acting as huge triggers. Pay attention if you transition into wind-affected terrain, and look and feel for sudden changes in snow surface texture and hardness. Carefully assess recent and wind-blown snow as you travel using hand pits and test slopes, looking for easy fractures and shooting cracks. Avoid travel on or below large wind-loaded slopes 35 degrees and steeper and minimize exposure to overhead hazard.

    (2/22/2021) Natural avalanches on Shuksan Arm breaking 2-3ft+ deep and hundreds of feet wide. Photo: Ben Williamson

  • Loose Wet

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    1

    Cold, low-density snow will see sunshine for the first time following a multi-day storm event. Expect the sunniest skies and the best chance for solar-triggered loose avalanches in the morning before high clouds move in by the afternoon. The loose wet problem may or may not materialize, but be on the lookout for rollerballs, pinwheels, and snow shedding from trees and rock bands. Loose avalanches could be dangerous on their own, and could even trigger slab avalanches as they run downslope. If you find evidence of wet and weak snow surfaces, seek out lower angled or shaded terrain. 

    (1/23/2021) Example photo of loose wet avalanches in steep rocky terrain.

Avalanche Discussion

Expect clear and dry conditions Wednesday morning before the next round of heavy precipitation returns late in the day. New snow still needs time to settle and stabilize, and a conservative approach to terrain is recommended. Carefully evaluate the snowpack as you travel. Watch for recent avalanches and steer clear of similar slopes. 

A widespread avalanche cycle occurred Sunday night and Monday with numerous large to very large natural avalanches reported throughout the West North Zone. Most notable was a very large natural avalanche that hit Hwy 20 crossing both lanes outside of Newhalem near Gorge Dam. Avalanches on Shuksan Arm were also impressive, breaking 2-3ft+ deep and propagating hundreds of feet wide. Poor visibility limited observations on Tuesday.

During the ongoing Covid-19 pandemic, continue to follow the latest guidance from local, state, and federal health officials. Avoid unnecessary risks that could impact first responders and stress medical resources.  Wear a mask when appropriate, practice social distancing, and consider recreating closer to home.

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