Bollettino valanghe

East Slopes South

Northwest Avalanche Center
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Pericolo valanghe

Sat
Alta quota
2 · Moderato
Limite del bosco
1 · Debole
Sotto il limite
1 · Debole
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In sintesi

Avalanche danger will be lowest in the morning after a mostly clear night and solid freeze. As the daytime warms up, loose wet avalanches may become possible on steep slopes in direct sun. Plan to move away from steep slopes that become unsupportable and wet. Steep wind loaded terrain at upper elevations still warrant some degree of caution for lingering potential to trigger an old wind slab over a weak structure.

Problemi valanghivi

  • Loose Wet

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Possible
    Dimensione
    1–1.5

    In the morning, the snow surface will have a thin crust and avalanche danger will be lower. The likelihood of wet avalanches will increase with direct sun and warming temperatures in the afternoon. Most avalanches would be small, but they could run naturally off steep rocks and cliffs, so be aware of the terrain above you. You could also trigger these slow-moving but heavy avalanches in steep terrain. If you begin to sink deeply into wet, sloppy snow or see active rollerballs, consider moving to lower-angle slopes or sticking to more shaded aspects. 

    (1/28/2024)

    Example of small wet loose avalanches shedding off cliffs in the sun.

    S Fork Manatash Creek. 

    Photo: Katie Warren

Avalanche Discussion

Friday should be a beautiful day in the mountains. We don't expect much afternoon cloud buildup, so temperatures should rise a notch or two higher than the highs on Thursday. Once the snow surface becomes mushy and unsupportable it'll be time to change aspects and look for more shaded slopes to recreate on. 

Forecasters were out on Thursday and found weak structure with rounded facets over the stout crust from early February. However weak, the weak layer did show signs of rounding and strengthening. Still, it'll be worth exercising caution in upper elevation terrain with dry snow that appears wind loaded. Stiff wind-textured surfaces can point you to potential wind slab locations. You can also use quick hand pits to feel for stiff over soft snow and observe the bond with underlying crusts. When in doubt, reduce your uncertainty by choosing well supported or more simple terrain. 

Since February 14th, storms have brought 14-16 inches of snow to the East South zone. In much of the region, this new snow now sits over persistent weak layers of faceted snow over the slick Early February Crust (EFC). Observers in many areas of the Cascades, including in an NWAC forecaster in the Darland Mt area last week, have found weak, faceted snow just above the stout EFC crust and also over a thin, breakable crust buried on 2/14 on southerly aspects. This persistent weak layer has produced avalanches in neighboring zones (observation here). Since February 15th, 13 unintentionally human-triggered avalanches have failed on or just above the EFC throughout the Washington Cascades. We have reports of avalanches on all aspects between 5000ft and 8000ft. It has been a number of days since the last reported avalanche, but these problems can be tricky and linger in certain spots like steep, rocky terrain with a shallower snowpack.  

Expect a very thin snowpack at lower elevations and on some steep southerly slopes. Slick crusts, exposed obstacles, open creeks, and bare ground continue to make travel more adventurous. 

Your avalanche, snowpack, or weather observations are extremely valuable to the avalanche community. Help create a more accurate avalanche forecast by submitting your observations here. 

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