Avalanche forecast

West Slopes North

Northwest Avalanche Center
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Avalanche danger

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Out of date — this forecast expired 2 years ago.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

Highlights

Look for a transition from wet and rainy to snowy, more winter-like weather. Fresh snowfall overnight into Sunday morning brings an increased chance of triggering an avalanche in layers of new snow. Start the day with a conservative mindset and choose lower-angle terrain to minimize risk. 

Avalanche problems

  • Storm Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Likely
    Size
    1–2

    Look for 8-16 inches of new snow by midday Sunday depending on your location within the forecast zone.  The best time to trigger an avalanche in new snow layers is during or immediately after heavy snowfall. You are more likely to trigger a fresh slab on slopes where the wind built thicker slabs. Given the quantity of new snow in the forecast, it would be wise to assess stability on all aspects instead of just focusing on wind-loaded terrain.

    Tracking new snow depths should be easy with a soft rain crust below the new snow. Use a ski pole or simply dig down with your hand as you gain elevation and change aspects. Look for instability using test slopes, hand shears, and other simple tests. Shooting cracks are a sign you could trigger an avalanche if you head onto a steep slope. When in doubt just stick to simpler, sheltered, lower-angle terrain.

    Triggering a small avalanche on a test slope means you will likely find bigger ones on larger slopes

    Photo: Peter Durr

  • Glide Cracks

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Unlikely
    Size
    1.5–2

    Heavy rainfall produced glide avalanches on Saturday. Glide avalanches occur when the entire snowpack slides on the ground below. Cooling temperatures and no rain mean there should be fewer of them in the coming days, but they can still release well after it stops raining. The best plan will be to avoid traveling directly under cliffs still holding snow, glide cracks, or slopes with wrinkled snow. Periods of poor visibility could make it difficult to identify hazards in the terrain above you.

    Look for glide cracks and other unstable, sketchy-looking snow features. (Photo from previous winter).

    Photo: Ben Williamson

Avalanche Discussion

Heavy rainfall was the story Saturday morning until it transitioned to snow at mid-elevations around noon. Precipitation totals were not off the charts but what was significant was how much of it fell as rain instead of snow. Heather Meadows saw a total of 2.75” as of Saturday evening with 2.20” of rain. Other parts of West North saw totals well over 3” with similar rain-to-snow ratios.  One can expect to find a saturated upper snowpack below the new snow. Upper elevations likely have many feet of new snow in addition to what falls Saturday night.

Reported avalanche activity was limited to glide avalanches with no large wet slab or loose wet avalanches reported. Fresh cracks and other signs of glide were also reported. Observations were limited to the immediate terrain around Mt. Baker Ski Area and Heather Meadows, so more avalanches could be reported in the next few days as folks travel a bit farther with better weather conditions.

Regions covered