Bollettino valanghe

Snoqualmie Pass

Northwest Avalanche Center
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Pericolo valanghe

Thu
Alta quota
2 · Moderato
Limite del bosco
2 · Moderato
Sotto il limite
1 · Debole
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Non aggiornato — questo bollettino è scaduto 7 months ago. Stai vedendo condizioni passate, non il bollettino in corso.

In sintesi

Wet avalanche problems will be front and center during this week's warm spell. If you are sinking into moist snow past your ankle, be leery of slopes over 35 degrees. You may see avalanche potential ebb and flow as sunshine, clouds, and wind impact the zone. 

Problemi valanghivi

  • Loose Wet

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Possible
    Dimensione
    1–2

    Recent rain, high freezing levels, and sunshine. We're experiencing them all in quick succession, resulting in a warm and weak upper snowpack. So focus on wet avalanches this week. At upper elevations, over a foot of snow was on the ground before rain soaked it on Monday. That means slides should be larger and likely more reactive as you ascend in elevation. Down low, you may not see more than a few rollerballs, if that.

    As you travel throughout the mountains, you may see blocks of snow shedding from cliffs or rocky ledges during the heat of the day, creating slides on the slopes below. You may be able to trigger a wet slide yourself if you encounter moist snow on steep slopes. Whether by natural or human causes, once initiated, any wet avalanche could grow large as it descends. Don't get caught by one, especially near terrain traps. 

    The mountains will talk to you and let you know if these slides are becoming more likely. Look for new fan-shaped avalanche debris, snow shedding from natural objects, or fresh rollerballs and pinwheels. If the snow surface is moist and you're sinking in past your ankles, consider heading for lower-angle terrain while keeping an eye on the slopes above you.

Avalanche Discussion

Tuesday was our first day post-rain, as temperatures rose, but clouds held the sun in check. As we set our sights on Wednesday and the rest of the week, temperatures should continue to climb, and sunshine will eventually become more pronounced.

How much snow is available to slide? And will the warm temperatures result in a wet avalanche cycle? These are the questions that need to be answered. Luckily, you have the power to help answer them. 

If the sun is fully out, there's no cool breeze, and the snow surface is wet and punchy or producing signs of wet avalanches, you can hedge your bets that instability is on the rise.

You can also check how much snow is available for avalanches wherever you're recreating. Just dig down in the snow or stick your avalanche probe in to see how deep the January Drought Interface (JDI) is. That should be the first major crust you encounter besides any surface crust that forms overnight. At lower elevations, it may be on the surface. Up high, it could be down a foot or deeper. Just remember that you can't easily assess snow depth on slopes far above you, so use good travel techniques. Just because you're in low-level clouds doesn't mean upper elevation slopes aren't baking in the sunshine.

We expect all avalanche activity to be confined to the snow above the JDI, which could provide a good sliding surface for avalanches to run far distances. Although weak snow above the JDI has been identified, reports indicate it has already been wetted in most locations. This will help limit the potential for widely breaking or surprising avalanches. But keep an eye out for slab avalanches of any kind. If you see one, dial your terrain selection way back. 

This upcoming week will not help alleviate the travel hazards and "early-season" conditions that have plagued us most of the winter. Holes, creeks, bushes, rocks, ice, and bare ground are commonplace throughout the mountains.

Regioni coperte