Avalanche forecast

Stevens Pass

Northwest Avalanche Center
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Avalanche danger

Sat
Alpine
3 · Considerable
Treeline
3 · Considerable
Below
3 · Considerable
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Highlights

Another round of snow overnight and warming temperatures will maintain dangerous conditions. Use quick tests and small test slopes to check how easily the snow slides before committing to bigger pieces of terrain.  If you see signs of instability; fresh avalanches, snow that slides easily on test slopes, shooting cracks, stick to slopes under 35 degrees. 

Avalanche problems

  • Storm Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Likely
    Size
    1.5–2.5

    To avoid triggering an avalanche, steer around any feature that's steeper than 35 degrees near where you see obvious signs of instability like recent avalanches, shooting cracks, or snow that slides easily. Avalanches will be easy to trigger on steep, leeward slopes at mid to upper elevations. They may even be easy to trigger in wind-sheltered terrain, especially early in the morning. Watch for "upside-down," or harder-over-softer, snow making slab avalanches easy to trigger. Open slopes exposed to east wind will likely harbor some deeper drifted slabs. Avalanches on these slopes could be larger and more dangerous. Here, you can watch for wind transport and stiffer, thick pillows of snow as indicators of the danger.  

    Expect another 8-12" of snow for Friday, with most of it accumulating overnight. While I don't expect the same intensity of precipitation rates as the past two storms (1/16-17 and 1/11), the big change will be warmer temperatures than we've seen in weeks. The recent, January 16th interface, could still be a problematic layer, especially on sun-exposed slopes where you find a crust or harder snow associated with it. You'll find it 1.5-2 feet below the surface in sheltered terrain, and possibly 3ft below the surface on leeward slopes. As you travel through the mountains, you can dig quick, informal tests to look at this layer and see how easily the snow slides on it.

    (1/17/2024)

    A small skier triggered, storm slab avalanche. 5250ft, NW, Stevens Pass sidecountry

    Photo: Josh Hirshberg

Avalanche Discussion

Stevens Pass picked up over a foot of new snow by the end of Wednesday with intense snowfall rates and periods of strong west wind. Observers reported numerous triggered and natural avalanches in the new snow. On Thursday, winds shifted east and observers reported wind affected snow from both wind directions. The few reports we have from Thursday seem to indicate that the 1/16 interface is becoming difficult to trigger at low to mid-elevations near the top of Stevens Pass. In the East Central zone, observers still triggered avalnches on this interface on Thursday. While instabilities from the last couple days have been reported in the new snow, visibility was poor, and we really don't know what happened in larger pieces of terrain. 

During the last storm, on the 11th, some very large avalanches ran on deeper weak layers, notably within the Solsitce crust sandwich.  The recent storms could be enough to re-activate these deeper weak layers, especially in the eastern end of the zone. These very large avalanches could run full path and would be difficult to survive. It would be wise to stay away from large runout zones until we know more about Wednesday's avalanche cycle. The Solstice crust, is now at least 5 feet below the surface in much of the zone. Snow profiles have shown the weak layers to consist of faceted melt forms, and some snowpack tests have given sudden and propagating results. This speaks to uncertainty in the avalanche danger. The best advice is to let this storm play out and stay away from large, steep features where full-path avalanches could run. 

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