Avalanche forecast

West Slopes North

Northwest Avalanche Center
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Avalanche danger

Fri
Alpine
3 · Considerable
Treeline
3 · Considerable
Below
2 · Moderate
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Highlights

A big increase in temperature could result in large natural and human-triggered wet avalanches on Thursday. On the other hand, we may have less activity than expected, and danger could be lower. Pay attention to your surroundings: if you start noticing wet avalanches or many new rollerballs coming down, steer around steep slopes and terrain beneath them where avalanches could run to. Avalanches could become very large and destructive if snow gets wet enough. 

Avalanche problems

  • Loose Wet

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

    We're not quite sure how Thursday will play out. Temperatures will increase, and we've received 5 inches of water since Sunday night. This means upper elevations may have up to almost 5 feet of new snow, and some or all of it may wet avalanche, given the right conditions. It could start raining before the day is out, which may spike wet avalanche activity as well. 

    There's a chance we'll have a widespread wet avalanche cycle, and if so, avoid all avalanche terrain. Avalanches could grow large or even very large, gouging deep into the snow and running further than expected, especially in gullies. Or, conditions may stay subdued, and there may not be any remarkable activity. 

    Regardless, wet avalanches are usually the easiest ones to monitor and manage. For starters, this isn't a day to commit to routes where you can't avoid avalanche terrain. You can do your part by monitoring slopes: 

    • If there are large natural avalanches running, then keep it simple and avoid steep slopes and the terrain beneath them
    • If there are no or few natural avalanches, you may still be able to trigger one on a steep slope. If you enter steep terrain, be cognizant of your surroundings and always have an exit strategy. Don't let one surprise you from behind because you will probably get trapped in it, which quite possibly will kill you. 

    Example photo: Large wet avalanches could result on Thursday, like these ones from a week ago at Hidden Lakes area. They frequently originate by rocks or trees. Photo: Val

  • Storm Slabs

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

    It's not out of the question that you could trigger a storm slab avalanche on Thursday. This is especially the case as you climb higher, where we have less information and temperatures have stayed a little cooler, preserving any storm instabilities for longer. 

    There was less slab avalanche activity than expected on Wednesday, but given how much snow we just received, it doesn't feel right to remove the avalanche problem just yet. Large natural slab avalanches from Tuesday night were observed near Mt Shuksan, in north-facing terrain at about 4500ft. Human-triggered avalanches were reported in the Twin Sisters, where temperatures stayed a little cooler and new layers were shallower. 

    Failures will probably be shallow, but they could occur deeper, given the large amounts of new snow. We believe most instabilities have settled out, but if you choose to travel in steep terrain there's still the slimmest chance you could trigger a small or large slab avalanche. 

    (4/9/2025) Large slab avalanches naturally ran Tuesday night on the flanks of Mt Shuksan at about 4500ft, north-facing. The largest arrow points to the crowns, other arrows mostly point to debris. Photo: Irene Henninger

Avalanche Discussion

Glide avalanches are still a concern not to be taken lightly. Cracks may be disguised beneath the new snow layer, but there hasn't been much of a cooling since we had warm temperatures and an abundance of rain. Now the old snow is insulated by several feet of snow at mid and upper elevations. Consider avoiding travel beneath gaping glide cracks, and large, saggy cornices too. 

Observers were out in the Baker backcountry, Canyon Creek, Twin Sisters, and Schriebers. Small human-triggered slab avalanches were reported between tracks at Schriebers, and human-triggered slab avalanches were reported in the Twin Sisters. A large natural slab avalanche occurred in the Baker backcountry Tuesday night. Wet loose activity ranged from rollerballs to small avalanches in the Baker backcountry, Canyon Creek, and Twin Sisters. We've got unusual spring conditions right now, and things are changing quickly day to day. Be sure to pause and evaluate before stepping into steeper terrain. 

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