Avalanche forecast

East Slopes South

Northwest Avalanche Center
View on map

Avalanche danger

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Out of date — this forecast expired 2 years ago.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

Highlights

Weak layers in the snowpack are slowly healing with calm, dry weather. You can look for signs of instability such as cracking, collapsing, and recent slab avalanches but dig down into the snowpack even if you don't see any to investigate the layers within. The best way to manage avalanche hazard will be to simply avoid steep, open slopes.

Avalanche problems

  • Persistent Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    2

    A weak layer of surface hoar buried 1-2 ft deep has shown fewer signs of reactivity. This problem will be most problematic in areas where the slab overlaying the weak layer is bigger and more cohesive. Persistent slab avalanches can break in surprising ways across terrain features. You up the chances for a perilous surprise if you step out blindly into steeper, more consequential terrain. You probably won't see any signs of instability on the surface before triggering an avalanche so testing for the buried weak layers can reduce your risk. Surface hoar can be identifiable as a thin gray line in the upper snowpack and with snowpit tests. You can reduce your risk by choosing slopes that are more planar without convexities and cliffs. Ultimately, the best way to manage the problem is to just avoid open slopes steeper than 30 degrees.

    (1/7/2025)

    Small rider-triggered wind slabs in the Superbowl that likely failed on the layer of buried surface hoar.

    (6800, ENE)

    Photo: Payton Schiff

Avalanche Discussion

Saturday morning, a group of four backcountry tourers were involved in an avalanche accident near Kendall Peak in the Commonwealth Basin area of Snoqualmie Pass. Details are still being gathered, but the accident occurred on a SW aspect at 5600ft. All four members were caught and carried. Two were injured. The party called 911 to request assistance. Search and rescue responded to the area and brought the victims to the trailhead.

This period of high pressure we are in will do an excellent job of healing the persistent slab problem soon. We unfortunately can't give more specifics due to a lack of on the ground data. Your best strategy is to make like a forecaster and dig around on many aspects to look for weak layers and unstable test results. Be sure there is no buried surface hoar before high-marking or sledding on steep slopes with convexities and terrain traps. If you get out in the coming days, we'd love to hear if you still found buried surface hoar or reactivity in the snowpack. Public observations are essential for NWAC forecasters to build more informed forecasts. Please help us reduce uncertainty by submitting an observation.

Especially on slopes that see direct sunshine, you may encounter surface snow that is warming and weakening. Snow shedding off cliffs/trees and rollerballs/pinwheels indicate that the snowpack is losing cohesion and beginning to move. If you begin punching deeply through the snowpack and the snow feels heavy and sticky, consider moving to shadier slopes.

You may find isolated pockets of wind-loaded snow in exposed terrain closer to the Cascade Crest. Cornices and harder, uneven snow surfaces will help point you to where these areas may be. If you're getting cracks shooting from your sled, dial back your terrain choices to more sheltered terrain.

Regions covered