Bollettino valanghe

Stevens Pass

Northwest Avalanche Center
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Pericolo valanghe

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

Recent storms and windy conditions mean you could trigger avalanches in small, shallow wind-drifts. These are likely isolated to the highest elevations in very steep terrain or confined gullies. In extreme terrain, even small avalanches can have high consequences, so when in doubt, default to more conservative terrain.

Problemi valanghivi

  • Wind Slabs

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

    The recent storms didn't bring much moisture, and with warm temperatures, most elevations saw more liquid than frozen precipitation. But at the highest elevations, small wind slabs may have formed on lee slopes below ridgelines. If you find stiff wind-drifts deeper than about 6 inches, you could trigger small avalanches on steep slopes. These may not be a problem on their own, but if you're in terrain where a small avalanche could push you over rocks or cliffs, the consequences could be significant. 

    Look for textured surfaces, cornice formations, or pillowlike drifts to identify likely wind slab locations. Use quick hand pits or small test slopes to observe how wind-drifted snow behaves. If you observe cracking or if the snow slides easily on underlying layers, avalanches are more likely. 

    (11/30/2024)

    Small confined features like in this photo are the most likely places to trigger a small wind slab on Saturday. 

Avalanche Discussion

Another meager storm will blow through the region overnight on Friday. Even if the PNW convergence zone favors Stevens Pass, we'll likely only see a couple of inches of fresh snow. There is a chance of sun in the afternoon, so wet avalanches on steep, sunny slopes are possible. While wet loose avalanches will generally be small and predictable, it is still best to avoid steep slopes if the snow feels wet and heavy. Cornice falls and glide avalanches are less likely, but always an unpredictable hazard. Avoid traveling under overhanging cornices, open glide cracks, or cliffs still holding slabs of snow.

I was out near Skyline Lake on Friday and found that this week's snow is still wet, but a semi-supportable surface crust and lack of significant sunshine limited any wet loose activity. Unfortunately, the wet snow below the crust created challenging travel through breakable crusts. There was just a trace of new snow over this crust. The surface was supportable to skis but not boots. On Thursday, Stevens Pass ski patrol reported a superficial overnight re-freeze with small natural wet loose avalanches out of steep, rocky terrain. Over the past week, there have been reports of cornice failures and open glide cracks. The upper snowpack has transitioned to melt forms, but make sure to monitor how frozen these upper crusts are during the warmer days with limited overnight cooling. If you are punching deeply into wet snow, shed style avalanches from cornice falls, glide cracks, or rock slabs are more likely. 

The spring weather creates dynamic and variable snow conditions. Conditions at lower elevations may feel like full springtime, but as you climb into alpine terrain, you can quickly find a return to winter and dry snow problems. Travel with an assessment mindset and be prepared to assess conditions as they change with time, elevation, and aspect. 

Significant uncertainty exists at this time of year as observations become sparse. You can help contribute to the forecast by submitting observations and letting us know what you see in the mountains.

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