Avalanche forecast

West Slopes South

Northwest Avalanche Center
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Avalanche danger

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

Plenty of recent snow, coupled with increasing winds, will maintain heightened avalanche conditions on Wednesday. Steep, complex. and rocky terrain, especially where slopes are wind-loaded and/or unsupported are the most likely locations to trigger a slab. Safer conditions and excellent snow can be found on lower-angle runs outside of the wind zone.  

Avalanche problems

  • Wind Slabs

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

    Another shot of snow overnight Monday into Tuesday was likely formed into fresh wind slabs. While we expect many of these slabs to stabilize by Wednesday, some could still prove reactive. Wednesday, increasing winds may form new shallow wind slabs, and it will be possible to trigger both older and freshly formed slabs, regardless of whether they are technically wind-loaded or not. 

    Slopes below steep ridgelines or cornices, entrances and sidewalls of confined gullies, rollovers, unsupported slopes, aprons below cliffs, and rocky outcroppings are all likely trigger points. If you see blowing snow, avoid any steep slope where it is landing. Look for drifts, textured surfaces, and lens-like deposits, but keep in mind that much of the snow surface is only minimally wind-affected making it challenging to identify everywhere that could be harboring a potential soft slab. What's more, slabs in wind-sheltered terrain are less likely but not out of the question in isolated locations. Feel for dense over less dense snow, look for cracking in the snow surface, use hand pits, uptrack tests, and small test slopes to gauge slab behavior, and retreat to simple and lower-angle terrain if any of your assessments yield results. Most avalanches should be small, but carefully consider the consequences of a slide on the piece of terrain you are eyeing and choose simpler terrain with clean runouts to minimize the impact of a potential slide.   

    (3/14/2025)

    A skier-triggered, shallow slab in confined, rocky terrain. This one propagated down the side of the chute and sent debris down the choke.

    Photo: Morgan McGonagle

Avalanche Discussion

Another 6-8" of cold, "blower" snow fell Monday night into Tuesday near Crystal Mountain, with lower totals elsewhere in the zone, Mt St. Helens and Mt. Adams excepted. If you venture to the Southern Volcanoes, you may find more dangeous avalanche conditions. The bulk of the precipitation from the storm system inbound Wednesday should fall after the day ends, but if the flakes start to fly earlier or increasing wind blows around soft surface snow, danger could increase earlier in the day.

We have limited new data from the West South, but in general, stability seems to have improved compared to a few days ago. All these recent storms have left a couple of feet of new snow, including several interfaces and even a few crusts on sunny aspects. Broadly speaking, the new snow is generally right-side-up, but has proven capable of producing slab avalanches, especially in close proximity to the storm.  The general pattern over the past week has been for an uptick in avalanche activity with each new load of snow, followed by a stabilizing trend, until the next round of precipitation. Most avalanches have been small and within the recent storm snow, however, with so much recent snow, we can't fully rule out avalanches breaking into deeper snow layers. 

Let's step back and look at the bigger picture. It's spring (almost), and the weather is complex. Winds are blowing from all directions, sun and clouds bounce back and forth over the mountains, and potent storms continue to impact the zone. This dynamic weather creates a snowpack that is highly variable depending on elevation, aspect, and slope character, leading to differences in snowpack structure that are difficult to detect, and even more challenging to predict their impact on the avalanche situation. One slope may be stable while another right next door may not.We have had at least 8 catch and carries with multiple partial burials over the past week in all of our zones. Thankfully, there haven't been any serious injuries, but that is beside the point. People, including multiple avalanche professionals, are getting surprised by and caught in avalanches. Most, but not all of these slides are breaking in quite steep terrain. Consider this before you step out into committing terrain and ask yourself, what will happen if I'm wrong?   

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