Avalanche forecast

West Slopes South

Northwest Avalanche Center
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Avalanche danger

Sun
Alpine
2 · Moderate
Treeline
2 · Moderate
Below
1 · Low
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Highlights

It got hot on Friday, snow got sloppy and wet, and it's going to get hotter on Saturday. We expect less of an overnight crust, so be forewarned that snow will probably loosen quickly in the morning. You could trigger an avalanche on steep slopes where you sink down more than a few inches, and shed-style natural avalanches from rocky areas and cornices will increase in frequency. 

Avalanche problems

  • Loose Wet

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

    If you have an early start there may still be enough of a crust at the snow surface to hold avalanche activity at bay for a period. It won't take long for avalanche activity to begin. When you start noticing the snow softening and any snow sliding, it's time to retreat from areas where you might trigger a slide or slides could run down onto you. 

    There are two varieties of wet avalanches to remain alert for on Saturday. As the snow surface softens, you may push loose slides in steeper terrain. Often, we think about wet, sticky snow deeper than your ankle as the threshold. These slides should generally be small and easier to manage. However, they can carry you over a cliff,  into a creek, or bury you in a gully if you’re not careful. 

    It's hard to tell if and when we might start seeing an uptick in spring shed activity. It hasn't happened yet, but any day now more activity might start. You might see a few isolated larger natural wet avalanches. Cornice, glide, wet slab, and gouging wet loose slides could all occur. This version of wet avalanches is very difficult to predict but much more consequential. Look for routes that help limit your exposure to looming cornices or blocks of snow clinging to rocky faces. These things could fall down with little or no warning.  They might happen before the day warms up. If you start to see larger shed-style events, or it just starts getting really hot out, get out of terrain where you have limited options for avoiding large paths that travel beneath features of concern.

    Example photo: Small or large avalanches may fail naturally or with a human trigger. Avoid traveling underneath where an avalanche may run down. 

Avalanche Discussion

Sure, the weather feels like spring, but the snowpack hasn’t fully made the shift. Mid and lower elevations and all steeper, sunny slopes have become warm and more uniform. Elsewhere, the snowpack is still layered and relatively dry. Until it fully transitions, we could be in for a few surprises. While not as big or widespread as some years, cornices still overhang many alpine ridgelines. They could sag and fail during this warm weather. You don't want to be on or under them if that happens. 

The upper snowpack consists of recent snow over the Early April Crust. Much more snow fell on the volcanoes than closer to the crest. In some places, it may be 1-1.5ft deep. As a result, you could see larger and more dangerous slides on the bigger mountains. It's getting much harder to find dry snow, but pockets on true north slopes at upper elevations may still exist. At this point, any wind slabs are several days old and unreactive. Even still, don’t ignore an obvious pillow-like drift in high-consequence terrain. If you ascend above our forecast area (8000ft), wind slabs could become more common. 

The lower-elevation snowpack is melting out quickly. This is particularly true on southerly aspect. Many areas are down to bare ground within the last month. Typically, continuous snow starts around 4500ft in shaded terrain. The lack of snow and faster transition to spring at these elevations helps limit the hazard. Any avalanche activty should be limited to a rogue block of snow shedding from rocks or a large avalanche descending from overhead. Open creeks, holes, bare ground, and obstacles are common at these lower elevations.

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