Bollettino valanghe

West Slopes North

Northwest Avalanche Center
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Pericolo valanghe

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

Around 6 inches of snow arrived Tuesday night, and despite the windy conditions there just didn't seem to be much of an an avalanche concern in wind-drifted layers. We have limited information from upper elevations, where small wind-drifted deposits may avalanche with a human trigger- especially as more wind redistributes low-density snow. Your main concern will be an increase in wet avalanche activity on steep slopes facing the sun as temperatures increase - or treacherous slick or bumpy hard surfaces beneath the new snow layer. 

Problemi valanghivi

  • Loose Wet

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

    A warm, sunny day will lead to moistening snow surfaces, rollerballs, and maybe subsequent wet loose avalanches. Much of the natural activity will likely be around rocky or shallow features, or possibly initiated from a tree bomb. Even if there isn't much natural activity, if you venture out onto a steep slope, you could trigger a wet loose avalanche, which may run easily on the old snow crust, about 6 inches deep.

    Pay attention to the sun's position and what steep slopes face directly towards it. These surfaces will likely moisten and surface layers could lose cohesion quickly. Depending on your timing and snow conditions, you may not get much activity, or, maybe many will slide. If snow around you starts getting wet, expect that you could trigger an avalanche if you're on a steep slope. Wet snow could slide easily on the underlying smooth crust. 

    If there is much natural wet avalanche activity or snow is noticeably wet, avoid traveling on steep slopes or beneath them where an avalanche could reach. 

    (3/5/2025)

    Rollerballs initiated as not long after the sun hit steep slopes that were directly facing the sun. There wasn't much for actual natural wet loose avalanches, just an abundance of small rollers. Baker backcountry. 

    Photo: Zack McGill - Cascade Mtn Ascents

  • Wind Slabs

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

    Light to moderate wind was present as the new snow layer arrived Tuesday night. Wind-drifted surfaces were visible, yet it just doesn't seem like they had enough of a slablike quality for wind slab avalanches to occur, even with a human trigger. Despite an abundance of slope testing from people in the Baker backcountry, only a few very small pockets avalanched.

    We have less information from upper elevations, where you should start conservatively and test small slopes and wind-drifted features before stepping out onto larger ones. Use hand tests to see how easily the slab slides on the underlying layer, most likely a crust. An increase in wind on Thursday may mean that more wind slabs could develop, and they might be more reactive than the previous day's. When in doubt, avoid steep, wind-loaded slopes. 

    (3/5/2025)

    The one small (D1) wind slab avalanche seen during a large outing. This was likely triggered by a cornice. Corner Pocket, Baker backcountry. 

    Photo: Robert Hahn

Avalanche Discussion

Even avalanches that may not be large enough to bury you could still kill you if you're caught in one or knocked over while you're above a terrain trap. Stop and reevaluate the snow before entering an area where you're above an abrupt bench or gully, over a cliff band, or patch of trees or rocks.

Other hazards that presented a concern on Wednesday were old, hard debris piles beneath the new, light snow layer. Small loose dry avalanches were also triggered by those who ventured out onto steep slopes. 

An atmospheric river bringing rain to upper elevations produced many large and very large wet avalanches February 21-23, some of which stepped down to the January Drought Layer 3-5ft beneath the surface. The storm concluded on the 25th with 1-2ft of dry snow and subsequent small to large storm slab avalanches. The storm totaled about 7 inches of water. By February 26, temperatures increased, and wet avalanches overwhelmed our forecasts for the next five days. The previously wet surface layers froze, and our current avalanche concerns are predominantly this shallow new snow layer. 

If you make it into the backcountry please share with us what you find by submitting an observation HERE or on the Avy app. 

Regioni coperte