Avalanche forecast

West Slopes South

Northwest Avalanche Center
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Avalanche danger

Mon
Alpine
2 · Moderate
Treeline
2 · Moderate
Below
2 · Moderate
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Highlights

As temperatures soar on Sunday, wet avalanches might occur on sun-exposed slopes. Look for moist surfaces or signs of instability such as rollerballs, pinwheels, or new avalanches as indicators that it’s time to head toward the shade. Be on the lookout for early-season hazards such as open creeks, exposed rocks, or partially buried trees.

Avalanche problems

  • Loose Wet

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

    A sharp rise in freezing levels could combine with a cold and layered snowpack to produce wet avalanches on Sunday. The bulk of the activity should be small loose slides on steep sun-exposed slopes. Look for precursors to wet avalanches such as rollerballs and pinwheels, or a wet and sticky snow surface to help you identify a shift toward higher avalanche potential. These slides often start at a point before fanning out as they move downhill. To manage this problem, you should head for shaded aspects, staying aware of slopes that could be basking in the sun above you.

    (11/29/2024)

    Small rollerballs occurred on steep rocky terrain in the sun. These are a great indication that wet avalanches could soon follow. 

    Photo: Dallas Glass

Avalanche Discussion

If it were springtime, we’d be waving our arms and shouting that this snowpack setup is primed for wet avalanche activity. But this certainly is not springtime. Sunday is the first day of December, meaning the days are short and the sun’s influence is both weaker and reaching fewer aspects. In mountain gaps or valley bottoms, an inversion could take hold, making upper elevations much warmer than what you experience when you step out of your car.

Head into the mountains with a mindset that this warmup has the potential to drive natural avalanche activity. Expect a different kind of day than we’ve experienced recently. Does that mean that’s going to be particularly dangerous? Not necessarily, but it will certainly be more so than Saturday. Remember that rapid changes in the weather are one of the influences that drive avalanche potential.

The snowpack around the West South zone is generally 4-6 feet deep at middle elevations and right-side-up. Reports of wind slab avalanches in the wake of last weekend’s storm have diminished as pleasant weather has graced our zone this holiday week. Still, be on the lookout for lingering pockets of wind-drifted snow if you're in shaded extreme terrain. On southerly aspects, a thin breakable surface crust formed on Thursday and Friday in many locations and could help to keep wet avalanche activity at bay as temps rise on Sunday. 

Even with an impressive snowpack to end November, early-season conditions still exist. Open creeks, downed logs, shallowly buried rocks, and numerous trees litter the landscape. Allow yourself extra time to deal with these potential hazards if you’re out enjoying the nice day.

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