Avalanche forecast

Snoqualmie Pass

Northwest Avalanche Center
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Avalanche danger

Tue
Alpine
2 · Moderate
Treeline
2 · Moderate
Below
1 · Low
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Highlights

Take a good look at the slope in front of you before committing to larger or more consequential terrain. E-S winds formed slabs in some unusual locations on Saturday. If you see any signs of drifts, wind lips, or pillow-like slabs then seek out an alternate, less wind-affected route.

Avalanche problems

  • Wind Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    1–2

    Small natural and human-triggered wind slabs were seen on Saturday and again on Sunday at the Pass. With this recent activity, anticipate wind slabs on exposed slopes at mid and upper elevations. Given the wind direction (E-S), you may find some of these wind-loaded pockets in strange places and on different aspects. Pay close attention near convex rollovers, along the base of cliffs, in the tops of chutes, and on the sides of mid-slope gullies. 

    Drifts, cornices, and textured surfaces could be your best clues to help highlight suspected wind-loaded slopes. In some spots, a few inches of soft fluffy powder could make spotting wind-affected snow a bit more difficult. Due to the strength of the recent winds, you may even find a small wind slab in the upper end of the below treeline band.

    (3/4/2023)

    Wind slab near Gold Creek/Rampart Ridge on Saturday 3/4.

    Public Field Report: Rampart Ridge

    Photo: Griffin M

Avalanche Discussion

The avalanche danger is slowly dropping after a rather stormy week. While you may encounter a passing shower, it shouldn’t have much bearing on the avalanche hazard. Since Saturday 2/25 around 4 feet of snow has fallen at mid and upper elevations near the Pass. An E-S wind event right at the tail end of the storm (3/4), redistributed the new snow and formed a fresh batch of wind slabs. We’ve seen a lot of these E-S wind events following storms this winter. They frequently result in more unintentionally triggered avalanches than normal because these slabs sit in places we aren’t often used to. 

The biggest question mark for Monday is the sky/sun and the possibility of loose wet avalanches. A new crust that formed on southerly aspects Sunday and a few more clouds should limit the potential for these wet slides. However, prolonged warm sunshine will result in the snow shedding from trees/rocks and triggering small loose wet slides. If you see new roller balls or tear-dropped piles of debris, expect natural avalanches from similar slopes. 

With unseasonably cold temperatures and so much new snow, travelers frequently reported deep conditions this week. Outside of wind-affected areas, the recent snow is right-side-up. Not surprisingly, avalanche activity has largely consisted of a few small natural and human-triggered wind slabs and loose dry avalanches. However, on Friday, one intentionally triggered small wind slab stepped down into older snow layers (2/25) and resulted in a large (D2) avalanche that ran 300 vertical feet. (2.5ft/80cm deep, N, 4300ft) While we think this is an isolated event, small facets and surface hoar have been observed on occasion at the 2/25 interface. An avalanche like this seems most probably in sheltered shaded terrain where those weak grains may have survived.

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