Avalanche forecast

West Slopes Central

Northwest Avalanche Center
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Avalanche danger

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

Loose wet avalanches are possible during periods of sun and warming. Move off and away from steep and sunny slopes if you see fresh rollerballs or other signs of wet avalanche activity. Use extra caution in very steep, wind-loaded terrain that could still hold fresh slabs of wind-drifted snow.

Avalanche problems

  • Loose Wet

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

    After two solid days of warming, settlement, and the start of a downtrend in temperature, the likelihood of wet avalanches should ease slightly on Wednesday. That said, this problem hasn’t gone away and remains worth keeping on your radar until things cool off more decisively. 

    Look for loose wet avalanches initiating in steep, rocky, treed, or cliffy terrain as the day warms. They should mostly release on sunny slopes, but some low- and mid-elevation shaded slopes may also warm up enough. Fresh rollerballs, pinwheels, or moist surface snow are the first signs that wet avalanche activity is increasing.

    Example photo: Rollerballs initiating from trees and other steep, rocky areas. These are indicators that more wet avalanche activity could follow. 

Avalanche Discussion

Stiff, triggerable wind slabs may still exist in steep, upper-elevation features. Use caution when transitioning into wind-exposed areas, especially in steep, high-consequence alpine terrain. This is most likely near the crest, where continued east winds have transported snow onto leeward slopes.

An NWAC forecaster traveling in mid-elevation terrain above the Middle Fork of the Skykomish observed widespread rollerballs and pinwheels but no avalanches, likely tied to sun and warming on Sunday or Monday. Snow surfaces were slightly damp on some mid-elevation northerly aspects, while temperature inversions kept most low-elevation snow surfaces cold and dry. The December 24 crust was found about 12 inches down, with generally right-side-up snow above it, aside from firm crust layers.

At Stevens Pass, warm air attempted to push in from the west, but cold air east of the pass held its ground on Tuesday. Solar input produced rollerballs and very small loose wet avalanches on steep southerly slopes, while shaded northerly aspects remained cold and largely unchanged. Moderate to strong easterly winds transported snow onto westerly aspects, though no wind slab reactivity was observed in traveled terrain.

In West North, a handful of small fresh loose wet avalanches were reported on the steepest sun-exposed slopes. Northerly slopes have remained cold but have settled significantly. Overall, warming, settlement, and time appear to be strengthening the snowpack, though surface conditions remain sensitive to sun and temperature.

Regions covered