Bollettino valanghe

East Slopes Central

Northwest Avalanche Center
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Pericolo valanghe

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Alta quota
3 · Marcato
Limite del bosco
3 · Marcato
Sotto il limite
3 · Marcato
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In sintesi

Additional rain and continued warming will maintain dangerous avalanche conditions. Wet avalanches that fail on deeply buried weak layers and break widely across terrain are likely. Make sure to choose conservative routes on low-angle terrain and avoid prolonged exposure to large open slopes overhead. If you're traveling in the Northern part of the zone, conditions may be more dangerous, and you should check the East North Forecast.

Problemi valanghivi

  • Wet Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Likely
    Dimensione
    2–3

    Avoid traveling on or near large, steep terrain features. Give yourself large margins of safety from potential runout zones. Wet slab avalanches can run further and break wider than you may expect. A good strategy is patience and conservative terrain selection. If you experience whumphing collapses, use extra caution to avoid steep terrain. However, you may not get warning signs before triggering an avalanche. 

    The snowpack is resting on a weak foundation. As we add rain and warming temperatures, snowpack conditions get even trickier. Wet slab avalanches are notoriously unpredictable. They often lag behind peak precipitation and can fail unexpectedly even after rainfall has ended. As liquid water impacts weak snow over the Solstice Crust, wet, heavy, and destructive slab avalanches are likely. Cornice falls and smaller wet loose avalanches could also step down to these deeper layers. 

    (1/24/2024)

    Very large hard slab triggered with explosives at Mission Ridge.

    Photo: Mission Ridge Ski Patrol

Avalanche Discussion

Saturday night will bring another round of moderate rain, and steadily climbing snow levels will hit 8500ft by Sunday evening. The snowpack is mostly dry at upper elevations, and we expect rain will initiate a widespread natural avalanche cycle overnight that may continue into the day. The timing of natural wet slab avalanches is always challenging to pin down. However, even as natural avalanche activity tapers off, you could still trigger one of these nasty avalanches. With scary, hard-to-predict avalanches, the take-home point is that until the snowpack experiences below-freezing temperatures, the potential for very large wet slabs remains. Consider the consequences of overhead hazard or triggering one of these deadly avalanches when choosing terrain. 

Further north, in areas near Holden and potentially the Entiat, even lower elevations still hold dry snow. Peak instability in these areas might linger further into Sunday. If you begin to see larger natural avalanches or any indications that smaller wet loose avalanches are initiating wet slabs, increase your margins further from avalanche terrain. Check out the East North forecast to help calibrate your understanding of the snowpack trends from north to south on the east slopes. 

Even the lowlands in the eastern foothills could see wet loose avalanches as rain and warm temperatures continue. 

The Solstice Crust/Facet Complex in the Wenatchee Mountains has been active since late December and has continued to produce avalanches. Mission Ridge Ski Patrol triggered some very large (D2.5-D3), hard slab avalanches on Wednesday and Thursday using explosives during avalanche mitigation work. These were from north and east-facing slopes below corniced ridgeline in the upper 6,000ft range. Human-triggered avalanches on this persistent weak layer have occurred on Jan 6th, 12th, 15th, 19th, and 20th. While these avalanches have primarily occurred in wind-loaded terrain, we can't rule out avalanches in sheltered terrain, especially since the storm snow above this layer is now becoming saturated. 

If you get out, let us know what you see by submitting a public observation!

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