Boletín de aludes

Stevens Pass

Northwest Avalanche Center
Ver en el mapa

Peligro de aludes

Sat
Alta montaña
2 · Moderado
Límite del bosque
2 · Moderado
Bajo el límite
1 · Débil
Open full map
Desactualizado: este boletín caducó 3 years ago. Estás viendo condiciones pasadas, no el boletín vigente.

Lo esencial

New snow and elevated ridgetop winds could create touchy slabs near and above treeline. Look for signs of slab development such as active wind transport and deeply drifted pockets in exposed areas as you gain elevation. Use less steep terrain if you find signs of instability or more than 8" of new snow. 

Problemas de aludes

  • Wind Slabs

    • Alta montaña
    • Límite del bosque
    • Bajo el límite del bosque
    Probabilidad
    Possible
    Tamaño
    1–2

    You'll probably find minimal danger at lower elevations, but conditions may change quickly the higher you go. They'll also change as the day progresses, with chances for a convergence zone to set up and deliver heavier snowfall late in the day.

    Look for signs of active wind transport and drifted snow. Blowing snow and fresh cornice development are a few of these. You can also use surface textures like wind etching and rippling to help decipher areas that may act as a cohesive slab. Check for shooting cracks and use small test slopes to see how wind drifted snow may react before going into steep, wind exposed slopes. Slabs may react differently depending on the slope- Most slopes will have a frozen crust beneath the new snow, but shaded north facing slopes could hold dry, weaker snow underneath. If you do find signs of instability, steer around more consequential terrain. 

    Example of a small wind slab near a ridgeline.

    Photo: NWAC Public Obs

Avalanche Discussion

We're snapping back to winter Thursday night into Friday with much colder temperatures, elevated ridgetop winds, and snow showers. Look for a solid freeze to form a supportable crust at lower elevations. The new snow may have variable bonds  to old surfaces, and as more snow adds up and the wind drifts it around on Friday expect a trend of increasing danger. If a convergence zone sets up over the area, we could see heavy snow with strong winds for a few hours late in the day on Friday and conditions could quickly become dangerous.

This past week we had an initial spring thaw, along with a prolonged cycle of wet loose avalanches and glide activity. Some slides were large, so expect to find frozen debris in many areas hidden under the new snow. On Tuesday and Wednesday the glide activity appeared to really ramp up. See photo below of a large glide west of Stevens Pass taken on Wednesday. Any slopes with glide cracks should be avoided, as glide avalanches have been known to release a few days after temperatures have cooled. 

Regiones cubiertas