Avalanche forecast

West Slopes North

Northwest Avalanche Center
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Avalanche danger

Tue
Alpine
2 · Moderate
Treeline
2 · Moderate
Below
2 · Moderate
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Highlights

The next storm begins Monday, depositing up to 6 inches during the day with moderate winds. You could find small new pockets of wind drifted snow at upper elevations, and warmer temperatures may contribute to small wet avalanches at lower elevations. Search for signs of wind-affected snow or wet snow surfaces, and avoid these areas on steep slopes.

Avalanche problems

  • Wind Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    1–1.5

    The snowpack is rapidly settling and strengthening with the warmer temperatures. Thicker slabs are evident on the surface, especially at upper elevations. They are mainly 6-10 inches deep, and many of the slabs found in the Baker backcountry on Sunday were unreactive. 

    Remain alert for wind slabs at higher elevations, and monitor slab development as snow falls throughout the day, possibly increasing their size and reactivity throughout the day. Search for active signs of wind depositing snow onto slopes, such as along ridgelines, below cornices, and on leeward sides of terrain features. Feel for thicker, heavier deposits of snow under your feet Avoid slopes greater than 35 degrees in these areas. 

    (1/9/2022) Textured, wind-affected snow surfaces in the Baker backcountry, a good indicator to be aware of the presence of wind slabs. Photo: Irene Henninger

  • Loose Wet

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    1–1.5

    I traveled around the Baker backcountry on Sunday before writing the evening forecast. Early in the day, small rollerballs ran down steep sunny slopes. By the time I returned at noon I only saw a couple very small, shallow wet loose avalanches, not large enough to do a person harm. I received reports of a couple more which ran a little larger later on in the day on the southern half of the compass. A thin crust will have formed on the slopes that got wet overnight, something to keep in mind for Monday. 

    Cloud cover and a slightly lower freezing level Monday (wavering in the 4500ft range) means that our wet snow problem will probably remain at lower elevations, but it could span the entire way around the compass, especially affecting low density previously dry snow on more northerly aspects. Check slopes around you to see if any rollerballs are running down. Search for signs of heavy, wet snow. Avoid steep slopes if you notice any of these signs nearby. Any avalanches will probably remain small, but stay alert for them especially if you're traveling near terrain traps where they could cause you more harm. 

    (1/9/2022) South side of Table Mountain area. Tiny little rollerballs ran Sunday morning occurred in the first few hours that the sun hit the slope. The rollerballs may increase in size and pick up more mass as temperatures increase. Then before larger swaths of surface snow could begin sliding down as wet loose avalanches. Photo: Irene Henninger

  • Deep Persistent Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Unlikely
    Size
    3

    In the West North Zone we are still suspicious of a layer of surface hoar buried on December 21st. It produced a handful of very large avalanches centered around the Shuksan Arm in late December.  We’ve had several storms since then and the layer is probably between 5 and 9 feet deep. These avalanches are very difficult for a single person to trigger. However, they could react to a large load like a  snowmobile, a falling cornice, or a smaller avalanche stepping down and triggering this deeper layer. Be aware that large deep slab avalanches from higher terrain could run into lower elevations where otherwise you might not expect to encounter a large avalanche.  I saw several old large avalanches on my Sunday outing which occurred during the storm in the last week. They were so filled in it was difficult to determine whether they just ran in the new snow layers or had stepped down to this underlying layer of concern. 

    (1/9/2022) Old avalanches which ran mid storm on Huntoon Point on a northeast aspect.  It is very hard to tell what it ran on- within a storm layer or deeper in the snowpack. This avalanche propagated several hundred feet. Photo: Irene Henninger 

Avalanche Discussion

A couple glide cracks are showing up around the West North zone. Stay alert for them as temperatures remain warm, as it's neither ideal to fall into one or have a glide crack avalanche on you as you're traveling beneath one. It's best to avoid areas below them if you see one.

A large storm came to a close on Saturday, with several feet of snow deposited throughout the zone. We’re now entering a smaller period of unsettled weather. The snowpack changed a lot lately, and is continuing to evolve extensively every day. Stay alert when you head into the backcountry as there is a lot of uncertainty with varying conditions spanning this very large zone. 

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