Avalanche forecast

Snoqualmie Pass

Northwest Avalanche Center
View on map

Avalanche danger

Sun
Alpine
2 · Moderate
Treeline
2 · Moderate
Below
1 · Low
Out of date — this forecast expired 2 years ago. You’re viewing past conditions, not the current bulletin.

Highlights

Snowfall totals might not catch your attention, but the wind speed should. You could find pockets of wind-loaded snow as you ascend into more exposed terrain. Give stiffer pillow-like drifts a wide berth, especially on higher consequence slopes.

Avalanche problems

  • Wind Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    1–1.5

    With only a few inches of new snow, these wind slabs might not be widespread or particularly large, but they may be in some weird spots, might trigger easily, and could catch you by surprise. Two things make this wind slab situation a bit different. 1: Winds differ by elevation and will change during the storm. This will make determining a consistent loading pattern very tricky. You could find slabs on some unusual aspects. Given the gusty nature of the winds, drifts may form well below ridgelines and along the sides of mid-slope features. 2. These wind slabs will form over a wide variety of old snow surfaces. This makes figuring out how any individual slope will react quite challenging. 

    Fortunately, any avalanche should be relatively small. Use your eyes to hunt for blowing snow or textured surfaces that indicate this problem. Be particularly careful if the slope is over a cliff or line of trees that might magnify the consequences of even a small slide

    (12/12/2024)

    A small crown from skiers intentionally triggering wind-drifted snow on a steep slope. 

    Photo: Andy Harrington

Avalanche Discussion

Southerly flow storms don’t favor the Pass. Instead of being a real snow producer, this will primarily be a wind event. Even still, it should add several inches to the thin early-season snowpack. Every little bit helps. Shallowly buried rocks, downed logs, open creeks, and even icy slopes still pose a significant hazard. 

This new snow will fall on a variety of old surfaces. Slick crust, wind-textured snow, soft old powder, and even a bit of surface hoar was reported around Snoqualmie Pass and in nearby zones. It's unlikely, but not impossible, that some of this weak old snow survived the onslaught of winds. This will be most likely in sheltered locations. 

Easterly flow at Pass level should weaken and turn westerly Saturday afternoon. This will result in a slight bump in temperatures. This could bring rain or wet heavy snow to Pass level for a few hours. At lower elevations don’t be surprised if you see a few piles of rollerballs. This shouldn’t create a real hazard unless they push you into an open creek.

Regions covered