Avalanche forecast

West Slopes South

Northwest Avalanche Center
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Avalanche danger

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

Avalanche danger is on the rise as heavy snowfall transitions to rain across the southern Washington Cascades. Large and destructive avalanches could be triggered from the weight of a person or occur naturally, particularly at upper elevations. Choose lower angle terrain, and avoid travelling near, or underneath large steep slopes. 

Avalanche problems

  • Storm Slabs

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

    The West South zone will see a wide range of snowfall totals from north to south, with the heaviest snowfall focused on the southern volcanoes. Avalanche danger will increase through the day, likely peaking during the afternoon as temperatures rise and denser snow falls onto lighter snow. You could trigger a large and destructive avalanche on mid and upper elevation slopes where preexisting snow coverage provides a sliding surface. Areas of wind-blown snow will further increase sensitivity, potentially resulting in pockets of deeper, more sensitive slabs. A natural avalanche cycle is also possible at upper elevations.

    Thursday will be a dangerous day across the West South zone. Step back from avalanche terrain as the day wears on and conditions worsen. 

    (2/18/2025)

    A natural slab avalanche was spotted Tuesday near White Pass ski area. NE, 6600ft. 

    Photo: White Pass Ski Patrol

  • Loose Wet

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

    Wet avalanches will become increasingly likely as rain intensifies, and recent dry snow begins to absorb water. Anticipate rain-on-snow up into mid-elevations. Wet avalanches require an old snow surface to slide smoothly, so the greatest hazard will exist in areas that had previous snow coverage before the storm. At the lowest elevations, fresh snowfall will collect on bare ground, limiting any avalanche hazard. Small test slopes and convexities are useful for assessing wet avalanche instability. If surface snow slides easily and entrains snow below, similar behavior may be expected on larger slopes. Once rain begins falling on snow, or the surface snow becomes noticeably dense and heavy, move to lower-angle terrain.

    (12/13/2025)

    A small fresh wet loose on a steep, SE aspect. If triggered, these slides can quickly entrain large amounts of snow, and run far down slope.

    Photo: Joe Dellaporta

Avalanche Discussion

A large amount of water is once again aimed at southwest Washington, but this time it will arrive as snow—at least initially. By Thursday afternoon, snow levels are expected to rise to around 6,000 feet, bringing rain to lower and mid-elevations. This is a dangerous combination for the volcanoes, where 1–2 feet of new snow could accumulate. Once rain begins falling on the fresh snow, conditions may deteriorate rapidly, and steep slopes could become unglued. 

This storm comes on the heels of a wild 24 hours of weather.  Rain reached into upper elevations on Tuesday and Tuesday night before quickly transitioning to snow early Wednesday morning.  6-10 inches of snow were recorded at mid-elevation weather stations on Wednesday in our zone. The winds were the true story, however, with peak 71mph and 114mph gusts at Paradise and White Pass, respectively.   With a variety of storm related impacts, we had no direct field observations other than the few webcams and weather stations still online right now.  

The weather over the past few weeks has been extraordinary, with torrential rains, extreme winds, flooding, and landslides. Many communities are dealing with damage to homes, infrastructure, and businesses, stretching resources thin. These events have limited access to the mountains for all of us. State and local resources are working diligently to reduce the worst of these impacts. We can help by being respectful of local communities, obeying road closures, and heeding ski area uphill travel policies.

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