Bollettino valanghe

East Slopes Central

Northwest Avalanche Center
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Pericolo valanghe

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

An increase in easterly winds may form shallow wind-drifted slabs where you could trigger an avalanche. While still unlikely, there is a chance that wind-loading might make larger avalanches on weak snow layers easier to initiate. Consider steering around steep slopes where you find deep drifts, particularly on northern aspects that harbor a weaker snowpack. 

Problemi valanghivi

  • Wind Slabs

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

    Wind slabs don’t seem to be widespread throughout the zone, but observers reported isolated pockets of wind-transported snow in the Salmon la Sac and Teanaway drainages. On Monday, an NWAC forecaster near Mission Ridge also found shallow fresh wind slabs. Identify wind-loaded slopes using visual clues such as cornice formations or textured surfaces and feel for stiff over weak snow. You can also use small, inconsequential test slopes to observe how the snow reacts. Cracking or mini avalanches are a sign you should avoid steep wind-loaded slopes. While these slides should be relatively small, they could trigger a larger and scarier persistent slab. 

    Human triggered small, isolated wind slabs in the Blewett Pass area on Saturday. 

    Photo: Payton Schiff

  • Persistent Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Unlikely
    Dimensione
    1.5–2

    The East Central zone hasn't had much activity or signs of instability on weak snow layers associated with the January Drought Layer in several days. An NWAC forecaster in the Mission Ridge area found the poor snowpack structure, but stability tests were largely unremarkable.  You're unlikely to trigger a persistent slab,  but these problems always come with a lot of uncertainty, especially with our widely variable snowpack. The distribution is nearly impossible to pin down, but the most likely places are on shady slopes where the winds drifted the snow deeper or closer to the Cascade Crest, where more recent snow accumulated. 

    Choosing simpler, well-supported, or lower-angle terrain is a good way to reduce your likelihood of triggering one of these slides further. Feel for stiff over weak snow and back off steep slopes if you experience the snowpack collapse audibly. 

    (2/3/2025)

    Example: A skier triggered persistent slab avalanche near White Pass. This slide released over a 100ft wide and 2-3ft deep.

    WNW, 5600ft SS-ASu-D2-R2-O

    Photo: Dallas Glass

Avalanche Discussion

Tuesday will be an extremely cold day, with wind chill values below zero. Make sure to pack extra layers and some hand warmers. It is also worth considering the consequences of a minor injury or equipment malfunction stranding you overnight in the mountains. A simple issue could quickly turn life-threatening. Thankfully, the sunshine will help moderate the frigid temperatures just slightly. It likely won't be warm enough to warrant wet loose avalanche concerns, but you could see some isolated dry loose avalanches off steep rocks warming in the sun. 

An NWAC forecaster in the Mission Ridge area on Monday found a few inches of fresh snow with a poor bond to the old snow surface of still wind-affected snow. Below these old 10-12inch wind slabs, is a weak layer of sugary facets from the January Drought. While the stability tests were unremarkable, this weak structure could come back to haunt us with additional snow. She also identified a layer of buried surface hoar 2ft deep that produced sudden test results. We expect the distribution of this more deeply buried surface hoar to be isolated, but it's still notable and another variable to track in our complex snowpack. 

On southerly aspects, avalanche professionals in the Holden area found a surface melt-freeze crust over 4-6 inches of recent snow well bonded to the old snow surface. 

At the lowest elevations and in the eastern parts of the zone, the snowpack may be very weak, but there hasn’t been much new snow. As a result, you’ll likely find general safe avalanche conditions and more exposed obstacles. 

Regioni coperte