Bollettino valanghe

West Slopes North

Northwest Avalanche Center
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Pericolo valanghe

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

Avalanche danger is trending downward as freezing levels drop.  If you encounter stout crusts at upper elevations, avalanche danger is further reduced. Continue to avoid travel beneath large glide cracks and under cornices, especially at mid-elevations and any areas without a surface freeze. Expect challenging travel everywhere, with exposed creeks and irregular, soft snow cover down low, and hard, possibly slick surfaces up high. 

Problemi valanghivi

  • Glide Cracks

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

    Glide avalanches are the main lingering problem as water continues to drain. Saggy cornices should remain on your radar as well. Visible glide cracks and large cornices are features to avoid traveling beneath. 

    Most wet avalanche activity is probably behind us. If a solid freeze exists underfoot, avalanche danger is more likely on Low. It's a gray area regarding how much of a freeze is needed to fully minimize wet avalanche concerns, as glide avalanches and wet slabs have been known to release despite a bit of a surface freeze. If the snow is frozen a couple inches thick, that's a good start at reducing the likelihood of an avalanche. 

    Example photo: Large glide cracks and runnels on Table Mountain in the Baker backcountry. Continue to avoid travel beneath large glide cracks like these. 

    Photo: Lee Lazzara

Avalanche Discussion

Near the top of our upper elevation band, there could be enough dry snow that you might be able to trigger a small avalanche. The new snow may be well bonded to the underlying layer. Moderate to strong winds, however, may have redistributed the dry snow into drifts. If you make it to upper elevations, investigate any drifts you find to determine the bond between the new and old snow layers. If small chunks break off and slide easily, there's a good chance that'll happen with larger deposits as well, so steer around them on steep slopes. 

Our last reports of large and very large natural wet avalanches were from the weekend. We suspect most natural wet avalanche activity has backed off but it's still not out of the question that a large natural avalanche could release as the snowpack drains. The problem is, although natural activity is trending unlikely, you never know when or where one may occur. Any lingering avalanche activity is most likely to happen in areas where a solid freeze has not yet occurred. 

We've seen about 5-8  inches of rain in the West North zone since temperatures soared, last Friday through this Thursday.  Snow cover is thin everywhere, but especially at lower elevations, for Groundhog Day. Snowpacks are averaging around 50% of what we normally see at this time of year. Creeks are swollen and there's snow lacking in many areas of the lower elevation band.  At most elevations, heavy wet snow, runneled surfaces, running water, exposed rocks/dirt, and avalanche debris now litter the landscape, making for challenging travel conditions. At higher elevations, yo'll probably encounter harder surfaces. 

Regioni coperte