Avalanche forecast

West Slopes South

Northwest Avalanche Center
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Avalanche danger

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

A combination of increasing wind, snow, and rain will quickly raise your chances of triggering an avalanche on Wednesday. Shifting, gusty winds near the Crest and heavier precipitation to the southern volcanoes will complicate the danger. As the storm intensifies, shift your travel plans toward wind-sheltered, lower-angle slopes.

Avalanche problems

  • Wind Slabs

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

    Wind drifts, and slabs will build quickly on Wednesday as precipitation intensifies and wind speeds turn up. Near the cascade crest and mountain gaps, stronger gusts are expected, with potentially flip-flopping direction. In most areas, any wind-blown snow will be deposited onto firm crust surfaces, which could provide easy sliding surfaces for avalanches.

    As usual, these slabs often form around and just below ridgelines, below cliff bands, and on exposed slopes. However, the shifting wind direction will complicate the distribution. You'll have to use active observations to identify where this problem exists. Look for active wind-blown snow, fresh cornices, and wind lips to identify wind-loaded aspects. If you find yourself traveling through unusually deep, dense snow, you may be in an area of wind-deposited snow. As the storm sets in, shift your travel from exposed, steep slopes to wind-sheltered terrain. At higher elevations, consider sticking to lower-angle terrain as conditions worsen. 

    (12/21/2025)

    A small wind slab avalanche on Panorama Point earlier in the season. These slabs often build up just below ridgelines or cliff bands.

    Photo: Andy Harrington

  • Loose Wet

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

    A period of warming on Wednesday will bring the possibility of wet avalanches. Fortunately, this problem should be confined to lower elevations with the warmer weather. It doesn't have to necessarily be raining for wet avalanches to occur; dense, wet snow can cause them as well. Wet avalanches will be increasingly possible as the temperatures warm, and cold snow falling from the sky turns warm and wet, eventually to rain.

    While you're out, keep an eye on the precipitation and temperatures. If you start to feel soggy, or you notice water dripping from the trees or jacket, wet avalanches may be on the rise. Move to lower-angle terrain as the day warms up, to limit your exposure. 

    (3/16/2026)

    Wet loose slides were spotted in the White Pass backcountry on 3/16. A result of rain on snow.

    Photo: White Pass Pro Patrol

Avalanche Discussion

Tuesday brought relatively calm weather to the West South. East winds increased through the mountain gaps, while high clouds limited solar input and kept the warming in check. No new avalanches were reported.

Wednesday’s storm system will bring a classic PNW storm day to the West South. All areas will see impacts, but Mount St. Helens sits in the bullseye, with significantly higher precipitation expected. An easterly component should also allow areas north of Mount Rainier, such as Crystal Mountain, to see more precipitation than usual. Wednesday's weather will change substantially from sunup to sundown. If you’re headed into the backcountry, stay flexible to changing conditions. As the storm intensifies, expect deteriorating visibility at upper elevations.

The current upper snowpack is fairly consistent across the West South. The surface consists of a few inches of drier cold snow on top of the 3/29 crust. The unmistakable, burly 3/25 crust is below, with old soft snow in between the two crusts. On northerly and shaded aspects, the 3/29 crust is thinner to non-existent. 

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