Avalanche forecast

West Slopes South

Northwest Avalanche Center
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Avalanche danger

Sun
Alpine
4 · High
Treeline
3 · Considerable
Below
3 · Considerable
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Highlights

Feet of snow, strong winds, and rising temperatures will maintain very dangerous avalanche conditions on the volcanoes on Saturday. Although you may find less natural avalanche potential near the crest, it will still be a dangerous day in the mountains. Avoid slopes over 35 degrees where triggering an avalanche is more likely, regardless of your location.

Avalanche problems

  • Storm Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Very Likely
    Size
    1.5–2.5

    Heavy snowfall and strong winds will rapidly load slopes on Saturday. There is plenty of snow available for transport. So look for thicker and potentially more sensitive slabs in leeward terrain. Widespread natural avalanche activity, resulting in very dangerous avalanche conditions is expected on the volcanoes. Regardless of your location, avalanches large enough to bury or kill you are likely.

    This week, multiple rounds of precipitation and wind have created numerous interstorm layers in the upper snowpack. Any number of these could fail on Saturday given the right slope and the right trigger. It's shaping up to be a good day to play around in the flats or trees, avoiding all terrain where avalanches can start, run, or stop. 

    (12/27/2024)

    A large natural avalanche in Pickhandle Basin near Crystal Mountain. This one has a clean look to it, meaning it likely occurred after the height of Thursday's storm.

  • Loose Wet

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

    Saturday's storm will be the warmest of the week, and temps may creep up high enough that rain falls on dry snow at lower elevations. If this happens, anticipate wet loose avalanches to occur. If it's raining or you see new rollerballs, pinwheels, or fan-shaped avalanche debris, head for lower-angled terrain, keeping aware of what's above you.

    (12/20/2024)

    Wet avalanches that occurred last week during a rain on snow event near Paradise. Watch out for wet activity if rain is falling on dry snow.

    Photo: Dallas Glass

Avalanche Discussion

The storm parade just won't quit for the West South zone. Not that winter enthusiasts are complaining. We are quickly building snowpack depth and are the first NWAC zone to reach 100 inches this season. With so much stormy weather, it's no wonder that avalanche conditions are dangerous out there. Reports of natural, human, and explosive-triggered avalanches large enough to bury and kill you have been rolling in consistently this week. Adding another 1-2 feet of snow on Saturday will only increase the potential size, sensitivity, and consequences of these slides. Winds well above the threshold to move snow into slabs will blow all day, even after the snow stops. It is shaping up to be a spicy day throughout the zone, but the volcanoes get an extra nod in the danger scale due to the larger snow totals expected.  Traveling in or near avalanche terrain on the volcanoes is not recommended.

On Friday, the NPS reported natural avalanches that hit the road to Paradise. Over at Crystal Mountain, backcountry travelers and avalanche professionals spotted several large avalanche crowns. They looked to of occurred at different times, some during the height of Thursday's storm while others may have been from Friday. Hand pits and small column tests highlighted interstorm layers that failed repeatedly and sometimes cleanly. 

The threat of natural avalanches will be lessened near the crest, but that doesn't mean it is non-existent. They will be more likely during or shortly following periods of heavy precipitation rates or strong winds, both of which are expected on Saturday. Work into terrain slowly and make good assessments before committing to a slope. Continued snowfall and winds will only expand the number of potential weak points but all avalanche activity should be confined to the snow above the easily identifiable Solstice Crust. It is likely buried 2-4 feet below the surface.

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