Lawinenlagebericht

Stevens Pass

Northwest Avalanche Center
Auf der Karte ansehen

Lawinengefahr

Thu
Hochgebirge
1 · Gering
Waldgrenze
1 · Gering
Unterhalb
1 · Gering
Veraltet — dieser Lagebericht ist 5 years ago abgelaufen. Du siehst vergangene Verhältnisse, nicht den aktuellen Bericht.

Kernpunkte

Exercise normal caution, you could still find some isolated areas of unstable snow in unsupported or consequential terrain at higher elevations. Consider the consequences of cornices as you plan your route, and again while you are out there in the mountains.

Lawinenprobleme

  • Wind Slabs

    • Hochgebirge
    • Waldgrenze
    • Unterhalb der Waldgrenze
    Wahrscheinlichkeit
    Unlikely
    Größe
    1

    Shallow wind slabs were created up until Monday the 1st in higher elevation and exposed terrain. These slabs are becoming harder to trigger with time. Still, it wouldn't be impossible to trigger a small, cohesive slab on high, shaded slopes on Wednesday. Be careful around unsupported slopes and in consequential terrain.

    Cornices can pose a significant hazard of their own. Keep these in mind as you travel, and limit your time beneath them. If there are sun breaks during the day, keep an eye out for moist, sticky snow and rollerballs. These are all good indicators that you could initiate small wet loose slides on steep slopes of similar aspects.

    (3/8/2021) Wind textured snow with a recent, shallow wind slab in alpine terrain of White Pine Cirque.

Avalanche Discussion

On Monday I observed a couple of recent, small wind slabs from alpine terrain on Mount Mastiff, and in White Pine Cirque (see photos below). Wind was visibly drifting at ridgeline from afar in the morning, and there was lots of wind textured snow at upper elevations. On Sunday observers reported shallow reactive wind slabs on Arrowhead.

Deep persistent slabs have become dormant, and we don't expect any of these over the next few days. The last deep avalanche in the zone ran around March 1, and we haven't had any suspected activity on the Mid-January crust layer responsible for these since around March 3 (West South zone). Since then we've gone through a warm-up, and cool down to help create thick melt freeze crusts on many aspects. However, to some extent the snowpack structure responsible for these can still be found, so don't be surprised to see more of these at some point as we move into the spring and summer. 

Last Monday, WSDOT avalanche teams triggered an 8ft deep D3 avalanche on the southeast face of Rock Mountain east of Stevens Pass (our last avalanche known to have failed on the persistent weak layer in this zone). In the Chiwaukum Mountains, a natural D3.5 avalanche in upper-elevation north-facing terrain is suspected to have run on Sunday. A massive avalanche (D4) ran naturally in the West Camp path on Rock Mountain a bit  over a week ago. Viewing the tree-laden debris gives you a taste of the destructive potential of that avalanche as you drive along Highway 2 east of Stevens Pass. 

During the ongoing Covid-19 pandemic, continue to follow the latest guidance from local, state, and federal health officials. Avoid unnecessary risks that could impact first responders and stress medical resources.  Wear a mask when appropriate, practice social distancing, and consider recreating closer to home.

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