Avalanche forecast

East Slopes South

Northwest Avalanche Center
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Avalanche danger

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

Cooling temperatures brought a return to mountain snow, with higher snow totals near the Cascade Crest. Moderate winds drifted this fresh snow into stiff slabs where you could trigger avalanches. Look for textured surfaces and pillow-like drifts near ridges to identify and avoid these wind-loaded features. 

Avalanche problems

  • Wind Slabs

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

    Near the Cascade Crest,  6-8" of snow fell along with moderate winds. Further east, snow totals tapered significantly but also experienced sustained winds in the mid-20 mph range. As a result, any recent soft dry snow easily drifted into wind slabs. We expect most wind slabs will be small, but with higher snow totals at the western edge of the zone, avalanches could be larger in these areas. The most likely locations to trigger a wind slab will be in alpine terrain near steep, rocky ridgelines and confined gullies. If you see large pillow-like drifts, shooting cracks, or the snow feels hollow beneath you, simply travel on lower-angle slopes or steer around these wind-loaded features.

    (4/1/2023)

    Shooting crack on a wind loaded test slope.

    Photo: Katie Warren

  • Loose Wet

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

    Wednesday is going to be quite cool, with partly cloudy skies. However, springtime cloud forecasts can be a bit tricky. If we see longer duration cloud breaks, we could see some wet loose avalanche activity. The April sun only takes a little time to warm snow surfaces, particularly in areas with fresh snow. We expect any wet loose avalanche activity to be small and isolated to steep, sunny slopes. However, near the crest, these slides may be larger. Look for rollerballs as an indication that snow is weakening and the likelihood of wet loose avalanches is increasing. If the snow feels wet and heavy, move to shadier slopes or lower-angle terrain. There may also be some lingering glide avalanche possible on smooth rock faces. So if you see a big frowning glide crack in the snowpack on steep, smooth terrain, give yourself a wide berth around these unpredictable avalanches. 

    (2/4/2023) Rollerballs like this are one of the first indications of weakening snow surfaces and wet loose avalanches. 

Avalanche Discussion

After a very rainy start to the week, Tuesday brought a welcome cooling and clearing trend for much of the East South zone. Further west, the rain turned to snow and piled up in some locations, particularly near Chinook and White Pass. The Bumping Lake area may have received up to 3-4" of new snow, while there was probably only 1-2" at Ahtanum Meadows. Overnight temperatures on Tuesday night will drop into the teens, likely forming a thick crust on surfaces at mid and lower elevations. The recent rain and warm temperatures changed the landscape a bit, and you can expect challenging travel and lots of bare ground at lower-elevation trailheads. 

If you get out into the East South, let us know what you see by submitting an observation!

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