Bollettino valanghe

Stevens Pass

Northwest Avalanche Center
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Pericolo valanghe

Tue
Alta quota
2 · Moderato
Limite del bosco
2 · Moderato
Sotto il limite
2 · Moderato
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Non aggiornato — questo bollettino è scaduto 2 years ago. Stai vedendo condizioni passate, non il bollettino in corso.

In sintesi

Monday will bring quiet weather with warming temperatures and sun. You can trigger avalanches on steep, sunny slopes and where the wind formed deeper snow drifts, just below ridges. Seek out shaded, wind-sheltered terrain or slopes under 35 degrees.

Problemi valanghivi

  • Wind Slabs

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

    Use caution on leeward slopes over 35 degrees where westerly wind deposited storm snow on the 10-11th. Along with typical drifting below ridges, you may find wind-stiffened snow in unsual locations and lower down slopes than normal. Avalanches could break widely across slopes and they could be easy to trigger in isolated areas. You can use simple tests like hand shears, test slopes, and tilt tests to evaluate the bond. Recent avalanches and cracks shooting through the snow are "red flag" indicators of the danger. 

    There's a chance that you could still trigger isolated avalanches in very steep wind-sheltered terrain. 7-9" of recent snow rests on a variety of thin weak layers including stellars, facets, or surface hoar over a crust. The crust is most prominent on steep southerly aspects and below 5,100ft.

    (1/11/2025) Crown of intentionally triggered windslab, NW ridge Tye Peak. Photo: Ryan Minton

  • Loose Wet

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Possible
    Dimensione
    1–1.5

    The sun and rising temperatures will warm the snow on many southerly slopes for the first time. Time your travel to be off of steep, sunny slopes before the snow gets wet and weak. If you see rollerballs or moist snow that slides easily, move to shaded or lower-angle slopes.

    (1/7/2025)

    Natural, wet loose avalanches in East Highlands Bowl last week. E, 5500ft. 

    Photo: Irene Henninger

Avalanche Discussion

After an active start to the weekend, observers at Stevens Pass reported indicators that the new snow is slowly gaining strength on Sunday. There were some isolated small avalanches and lingering signs of instability. An NWAC forecaster near Skyline Lake found numerous resistant and non-propagating test results and couldn't trigger cracking or unstable snow on unsupported convex features. They did find large facets, and to a lesser extent surface hoar, buried in some locations. The most problematic snowpack structure was on steeper, southerly aspects. The recent snow is cohesive and over 4-finger hard in some locations. 

On Saturday, observers triggered numerous avalanches in wind-loaded and sheltered terrain running on a weak-layer crust (1/10) interface. Observers in the Skyline Lake, Lichtenberg Mtn, Yodelin, and Lanham Lake areas all reported either triggered avalanches, propagating test results, or other signs of instability. Below last week's crust, there are no layers of immediate concern.

Let us know what you see when you're in the mountains by submitting an observation.

Regioni coperte