Lawinenlagebericht

West Slopes South

Northwest Avalanche Center
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Lawinengefahr

Thu
Hochgebirge
3 · Erheblich
Waldgrenze
3 · Erheblich
Unterhalb
2 · Mässig
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Kernpunkte

Recent avalanches indicate that the snowpack is still adjusting from the recent storm. Give it time to heal by sticking to slopes under 30 degrees and be sure to watch the weather for changing conditions. A whopper of a storm is heading our way and could reach the southern end of the zone by day’s end.

Lawinenprobleme

  • Storm Slabs

    • Hochgebirge
    • Waldgrenze
    • Unterhalb der Waldgrenze
    Wahrscheinlichkeit
    Likely
    Größe
    1–2

    There have been plenty of reported slab avalanches around the zone recently and we expect that trend to continue on Wednesday. Most slabs should be soft and within the recent storm snow, but in wind-prone areas, these slabs may be thicker and possibly more reactive. Digging in the snow with your hand or shovel can help you identify heavy over lighter snow or storm instabilities that could be a point of failure. Focus your efforts on the layers above the 1/2 interface, but keep the thought of deeper avalanches in the back of your mind. Using test slopes, quick hand pits, and uptrack tests as you travel may give you an indication of the bonding of the recent snow and the potential for slab avalanches. Red flag signs of instability such as shooting cracks, whumpfing collapses, or recent avalanches are a great indicator to dial back your terrain selection. When in doubt, avoid slopes over 30 degrees or areas where you are more likely to trigger an avalanche such as convex rollovers, the base of cliffs, or confined chutes and gullies.

    (1/4/2022)

    On all aspects, sensitive slabs were breaking 10-15" deep in the recent storm snow near White Pass. [N-E 6300']

    Photo: Dallas Glass

Avalanche Discussion

On Tuesday, NWAC forecasters near White Pass reported soft slabs about a foot deep on all aspects. Many of these slides were breaking lower in the start zone than expected and most were in the D1.5 range. Additionally, widespread cracking of the surface snow (a red flag sign of instability) was reported by both NWAC forecasters and White Pass Pro Patrol. Over at Crystal Mountain, slabs were reportedly less widespread than they were yesterday, but still running far distances and entraining snow up to size D2. 

These observations help to give us some confidence that most avalanche activity should be isolated to the recent storm snow (above the 1/2 interface) on Wednesday. That said, there are still some questions to be answered about deeper layers in the snowpack and the possibility of surprising avalanches, so ease into terrain slowly and be sure to do your homework. All of these layers should be put to the ultimate test on Wednesday night and Thursday as a major storm with elevated freezing levels and plenty of moisture heads our way from the south. The timing of this storm is a little bit in question, so be prepared for an incoming storm if you are out toward the end of the forecast period or in areas further to the south. Wednesday night will not be the time to spend a night in the mountains. 

The recent storm snow has again brought to light the dangers of snow immersion. You can read about this hazard here. As temperatures start to warm up with the incoming storm, take care around buildings and trees that will begin to shed large snow loads. Roofalanches and tree bombs are a real hazard that people have died from in the past.

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