Avalanche forecast

West Slopes North

Northwest Avalanche Center
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Avalanche danger

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

We’ve settled into a spring cycle with freezes overnight and south-facing slopes softening during the day. Firm conditions will make for challenging travel, but steep surfaces facing the sun will soften quickly. If you start sinking several inches deep through wet sloppy snow or see rollerballs coming down steep slopes, steer to areas with firmer snow.

Avalanche problems

  • Loose Wet

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

    One small wet loose avalanche was reported on Friday, running in very steep, rocky, south-facing terrain. This occurred once the sun softened the snow surface for a few hours. With slightly warmer temperatures Saturday, we may see a few more avalanches. They will mostly remain limited to steep, rocky, isolated areas, but if surfaces soften more, it is possible that you could trigger an avalanche in larger, open expanses. Likewise, one could start in a rocky area and fan out onto a broad slope. 

    As the sun softens surfaces, pay attention to how far you’re sinking into the snow. Notice rollerballs coming down steep slopes. If you start sinking in to your ankles, steer clear of steep, south-facing slopes. Move to northerly aspects or stay on slopes less than 35 degrees and avoid travelling beneath steeper locations. If you’re chasing good spring conditions you might be able to continue slowly shifting your aspect as the sun moves, maintaining travel on slightly softened surfaces.

    (2/11/2022) One small wet loose (point release) avalanche was seen Friday, originating in a very steep, rocky area of the south-facing aspect of Mt Herman in the Baker backcountry at about 4400ft. Photo: Sierra Bishop

  • Persistent Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Unlikely
    Size
    1.5–2.5

    We are uncertain about whether the persistent weak layer survived the warm, wet weather and subsequent surface freezing which occurred in the last few days. Buried 1-2 feet below the surface and found just above the Late January Crust, we saw occasional avalanches on this weak layer. They usually occurred in isolated pockets on north-facing slopes, with an uneven distribution on a slope-wide scale. 

    Until we know more, assume this problem still exists on upper elevation terrain on the northerly half of the compass. If there are several inches of a solid surface freeze, you probably will not trigger an avalanche on this layer. However, if you find areas with a minimal surface crust at upper elevations, the weak layer may still exist. So far, we’ve found that you can get away with traveling on many steep slopes without causing an avalanche, but there is a very small chance that you could trigger an avalanche on that layer if you find just the right spot on the slope. It’s important to consider this if you’re planning on heading to steep upper elevation northerly terrain.

Avalanche Discussion

The diurnal spring cycle is a welcome change after the warm, moist weather on Wednesday and Thursday, which wetted the upper layers of the snowpack. Large cornices could peel off in the warm weather we’re seeing right now, so stay alert if you’re moving near them. The firm, slick surfaces are difficult to travel on, especially if you venture into steep terrain. Plan your trip so that you are prepared to manage the hard snow.

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