Bollettino valanghe

Snoqualmie Pass

Northwest Avalanche Center
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Pericolo valanghe

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

A fresh shot of wind and additional light snow will keep the stakes raised at upper elevations Monday.   Continue to avoid big open slopes capable of producing large avalanches, sticking to lower angle and less wind affected terrain. 

Problemi valanghivi

  • Storm Slabs

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

    New snow and wind continue to drive the hazard in the Snoqualmie Pass area.  Shifting winds will easily transport recent low density snow overnight through Monday.  Recent storm instabilities from this weekend are healing with time but cold temperatures and suspect layers in the upper snowpack mean you need to tread carefully as you climb into more exposed and consequential terrain. Slab avalanches are more likely to break near the surface but avalanches may break down to lingering deeper layers.  Poor visibility, stormy conditions, and a building snowpack have limited direct observations this weekend.  We have more uncertainty than usual coming out of this storm cycle, so take a cautious approach when planning your day. 

    (12/11/2021)

    A small Storm Slab that likely failed as temperatures warmed on Saturday 12/11.

    Photo: Vetta Mountain Guides

Avalanche Discussion

On Sunday, snow continued to pile up slowly but consistently in the form of showers in the Snoqualmie Pass area. The few observations that did trickle in detailed the new snow that was less cohesive and reactive to ski tests than earlier in the storm.  However,  at least 1 shallow skier triggered storm slab failed on a graupel layer about 10" down in the Alpental area with more widespread human triggered storm slabs reported in the Stevens Pass area Sunday. 

Snoqualmie Pass has received almost continuous precipitation since 12/8, producing anywhere from 3-5 feet of new snow, more than doubling the depth of our early season snowpack.  The tragic incident near Crystal Mountain helps illustrate that although it is early season and snow depths are still building, many slopes have now reached the threshold where they can kill you.  Take the time to investigate the snowpack and let us know what you see out there by submitting an observation.  You'll find the stout Late November Crust several feet down in all areas now (see photos).  While all this snow is welcome for base building, you'll still find some early-season travel hazards below treeline in some areas.  Use care around open creeks and recently buried rocks and stumps. 

Preliminary Accident Report: On Saturday morning, December 11th, an avalanche fatality occurred in the Silver Basin area of Crystal Mountain Ski Resort.  See the accident summary for additional details.

Regioni coperte