Avalanche forecast

West Slopes North

Northwest Avalanche Center
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Avalanche danger

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

There's a chance you still might be able to trigger an avalanche in wind drifted snow that developed in the last couple days, and it may be more prevalent in some areas of the zone than others. Identify thicker, wind-loaded features and steer around them on steep slopes at upper elevations. The last couple days we've had sun and a very small amount of loose avalanche activity on south-facing slopes- this may continue Monday. 

Avalanche problems

  • Wind Slabs

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

    Small to large natural and human triggered avalanches occurred Friday while slopes were actively loading. A little continued wind slab activity continued on Saturday, and less on Sunday. At upper elevations there's still a chance  you could trigger a wind slab avalanche, especially in farther flung parts of the zone. 

    Some areas of the zone received more wind at than others, so you have to evaluate as you travel to determine whether there are still newly formed slabs that will react to a human trigger. Most avalanches will probably be small, but not much information exists from upper elevations and further reaches, and there's a chance you could trigger a large avalanche.

    Higher mountain passes and further east had more wind, so these locations are where you're more likely to find slabs lurking. No matter where you are, take the time to evaluate wind slabs before heading onto steep slopes. Use hand pits to evaluate for harder layers over softer snow and see if the hard layer easily slides on the underlying layer. Start with small features before heading onto larger ones. When in doubt, steer clear of slopes greater than 35°. 

    (4/3/2023)

    Example photo: Small pockets of wind slabs are what you're probably most likely to trigger on Monday. Note the wind featured foreground, a telltale sign that wind redistributed the snow. NNW, 6000ft in the Canyon Creek area. 

    Photo: Hans Brubaker

Avalanche Discussion

There may be a tiny amount of wet loose avalanche activity on steep south facing slopes midday.  The sun is forecasted to be out again, and temperatures are supposed to get a little warmer. We've seen sun the last two days, so you're likely to find a thin crust on steep southerly aspects early or late in the day. 

A few very large natural avalanches were reported at upper elevations around the zone in the last few days. We suspect the avalanches failed above the 12/30 crust on a weak, faceted layer of snow. The layer is probably buried 3-5+ feet, predominantly at upper elevations. No human-triggered avalanches have been reported on this layer, but think about it if you're heading onto large, unsupported upper elevation slopes as a low probability- high consequence concern: The weakness is probably buried deep enough that we don't suspect a human would trigger an avalanche, but maybe a snowmobile would. If you're on a shallower spot there's probably a higher chance you could trigger an avalanche on this layer.

I was in Bagley Basin on Sunday, and it was well loved by many backcountry enthusiasts. Weather was cold, calm and clear- except hot in the sun. Expect it to be similar on Monday. There was minimal new avalanche activity, although a few signs of old small natural and human triggered old slides on most aspects- some slabs, some loose, from the last few days. Some areas had a noticeable stubborn wind-stiffened surface, while other spots were blower powder. Steep south-facing aspects just barely got moist, and I found weak near-surface facets forming at the surface and a little surface hoar in places. Crusts were present where the sun angles weren't as direct. Similar conditions were reported on the south side of Baker from the motorized community on Sunday as well. 

 

 

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