Bollettino valanghe

East Slopes Central

Northwest Avalanche Center
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Pericolo valanghe

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

Welcome back! We are excited to kick off the 2024/25 season with you!

You could trigger avalanches in wind-drifted snow on steep slopes. Identify and steer around deeper drifts on steep slopes and rollovers, particularly in the Wenatchee Mountains with higher recent snow totals. While most avalanches would be small, they could still take you for a nasty slide through trees, rocks, and other early-season obstacles. 

Problemi valanghivi

  • Wind Slabs

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

    Recent snow and wind formed wind slabs at upper elevations along ridgelines and steep unsupported terrain. As recently as Monday, I and other observers reported reactive wind slabs failing on a melt-freeze crust formed in late November.  Wind slabs at upper elevations were notably more sensitive than in middle elevations, but we suspect you could still trigger an avalanche in terrain below 6000ft. They just might be more isolated.  Step into the terrain slowly and check the reactivity of the wind slabs on small, inconsequential test features before committing to any steep wind-loaded slopes. Shooting cracks, whumping collapses, and recent avalanche activity are signs that these slabs are unstable, and you should steer around these features in steep terrain. 

    We expect most avalanches to be small, but we have limited information in these early stages of winter. Most of our information is from the Mission Ridge area, which experienced significantly more snow and stronger winds on Sunday. So expect elevated avalanche hazard in this area compared to the rest of the East Central Zone. Even small avalanches could drag you through rocks, or cause falls with high consequences in these low snow cover conditions. 

    (11/25/2024)

    On Monday, ski cuts produced small, but energetic wind slabs. 

    Photo: Katie Warren

Avalanche Discussion

Welcome to winter! A parade of storms favoring the east slopes of the Cascades brought us a robust early-season snowpack. However, we might have to hold on to the memory of those storms while we transition into a drying weather pattern. Thankfully, the short term holds onto cold temperatures. But we could see a more significant warm-up this weekend. With the clear skies, you could see rollerballs shedding from rocks warming in the sun. But this time of the year, the sun is too low in the sky to cause significant snowpack warming. So, besides some rouge rollerballs, don't expect wet avalanches of much significance. Access at lower elevations is still challenging with low snow cover and many obstacles to negotiate below 4000ft. Snow depths increase rapidly with elevation, and 5000ft and above have snow depths of 3-4ft. The base of the snowpack is old consolidated snow from early November. Above this, there is nearly 2ft of unconsolidated storm snow.  However, fluctuating temperatures throughout the recent storms created a few melt crusts within the pack. These crusts are acting as a good sliding layer for avalanches. Recent storm and wind slab avalanches failed on top of these crusts. Low elevations still have shallow snow cover with challenging access and many hazards to negotiate, such as creeks, rocks, and fallen trees. With the difficult access, we still have limited information for most of the East Central. Be prepared to make your own assessments as you take advantage of the high pressure to push into different terrain. Watch for red flags such as collapsing, recent avalanches, shooting cracks, or whumphs. These are all signs you should stick to lower-angle terrain.  

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