Avalanche forecast

Snoqualmie Pass

Northwest Avalanche Center
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Avalanche danger

Fri
Alpine
3 · Considerable
Treeline
2 · Moderate
Below
1 · Low
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Highlights

More snow, wind, and spring temperatures will impact Snoqualmie Pass on Thursday. Expect slab avalanche potential to increase as you ascend in elevation toward drier snow. Wet avalanches could occur anywhere you find a moist surface on slopes over 35 degrees.

Avalanche problems

  • Storm Slabs

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

    As you ascend in elevation, the likelihood of dry snow problems increases. Slabs are still possible at elevations with moist snow, but they may be more stubborn. Use quick hand pits to check for layers of concern or a poor bond to the underlying crust. You may find heavy snow over softer snow due to fluctuating freezing levels, resulting in a storm slab problem. Look for textured surfaces or fresh drifts to help identify wind-loaded slopes. Uptrack tests and small test slopes can help indicate how these problems react to your weight as a traveler. You're more likely to trigger a slide on slopes over 35 degrees, so when in doubt, default to lower-angled terrain.

    (3/27/2024)

    A skier triggered storm slab avalanche on a convex slope at mid-elevations. This occurred in the neighboring West South zone on Wednesday.

    Photo: Dallas Glass

  • Loose Wet

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

    Thursday should be a notch warmer than Wednesday, meaning rain will reach higher, and existing snow will be heavier.  Look to the snow surface to help determine when and where wet avalanches could occur. If you are sinking into moist snow deeper than your ankle, see new rollerballs, or notice snow shedding from trees and rocks, you should anticipate wet avalanches. These slides often start small but can grow large as they descend and fan out. They'll likely be heavy and can be deceivingly powerful. Don't get tripped up by one near a terrain trap where the consequences could be amplified. 

    (3/24/2024) 

    A wet loose avalanche on a steep slope. It fanned out and grew larger as it descended. You don't want to get pushed around or knocked over by one of these.

Avalanche Discussion

We're not out of this snowy pattern yet. But it is on a downtrend.  Similar to Wednesday, another round of precipitation, wind, and fluctuating freezing levels are on tap for Thursday at Snoqualmie Pass. 

It was a stormy day at the Pass on Wednesday. The freezing level stayed lower than anticipated, but it was still quite wet out there. Even at mid-elevations, where the snow was drier, the relatively warmer spring temperatures meant it was just a bit heavier than if this storm had occurred a month ago. NWAC forecasters found roughly 15" over last week's warm-up crust with multiple failure points in the new snow. The snow was light and fluffy in the morning but got progressively heavier as the day wore on, resulting in a slightly upside-down snowpack. Backcountry travelers on Hyak reported moist snow resulting in widespread rollerballing. 

Over the weekend, observations relayed that a range of wet avalanche problems impacted the Pass. Wet loose and glide avalanches large enough to kill you were reported by backcountry travelers. Most of the bigger slides initiated out of rocky terrain and then gouged deeper into the snowpack. If the sun comes out, keep an eye on the terrain above you; similar slides could occur. 

At lower elevations, our snowpack has taken a beating. You'll likely find punchy wet snow, patchy coverage, and exposed creeks/holes. The new snow likely helped mask some of these problems, but it is only a matter of time before we're back in the same predicament. Avalanche potential should be minimal, but you could see some rollerballs or small piles in the damp new snow.

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