Avalanche forecast

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Northwest Avalanche Center
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Avalanche danger

Thu
Alpine
3 · Considerable
Treeline
3 · Considerable
Below
2 · Moderate
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Highlights

Wednesday's weather could be a wild one, with strong to extreme winds, new snow, and a warming trend.  Stay off steep wind-affected slopes at upper and mid-elevations, and be aware of your overhead exposure as the likelihood of natural avalanches ticks up during the day.  Stay off of very steep features at lower elevations if you find yourself sinking into heavy wet snow. 

Avalanche problems

  • Wind Slabs

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

    Even with a healthy dose of uncertainty about how Wednesday's storm will play out, your best plan is not to mess with wind-loaded terrain.  There's plenty of soft soft snow available for transport as SE winds increase and become strong to extreme on Wednesday. 

    You're likely to trigger an avalanche in wind-affected terrain, and you may find denser wind slabs building further downslope or on unusual aspects. Natural slab avalanches aren't out of the question.  Look for signs of increasing instability and if the hazard is on the rise, make sure you have simpler terrain to fall back on for a safe exit.  

    If the warm-up is slow to develop, you may find shallow fresh wind slabs forming along lower ridgelines in the drier/sagebrush parts of the zone.  There might be enough new snowfall during the day that shallow storm slabs come into play in more wind-sheltered terrain. 

    (12/23/2025)

    Several small natural wind slabs, like the one in this photo, were found below ridgelines in the Twisp River valley.  These likely occurred Monday night. 

    Photo: Katie Warren

  • Loose Wet

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

    Snow levels will slowly rise on Wednesday, and rain may push well into the lower elevation band. 

    If there's rain on snow or you find yourself stomping around in increasingly moist and heavy snow,  start thinking about wet loose avalanches.  Most wet loose avalanches would be small, so avoid locations where a small avalanche could do some damage near terrain traps. 

    Example photo: A small wet loose avalanche in thin snow cover, running down to the ground. 

    Photo: Irene Henninger

Avalanche Discussion

Backcountry travelers noted plenty of wind-affected snow in the Upper Chewuch and Twisp River drainages on Tuesday.  Strong winds on Monday night eased into Tuesday, and a few small natural wind slab avalanches likely occurred Monday night below ridgelines.     

Sunday night into Monday, winds drifted snow and formed fresh slabs at upper elevations. On Saturday, others reported a snow height of 6 feet at 6,700ft at the end of Twisp River Road. Observers east of the Cascade Crest reported 8-12 inches of recent snow at 4500ft, increasing to 2 feet above 5,500ft. The Harts Pass snotel station is reporting just over 100" height of snow. There, observers reported whumpfing collapses on Friday. 

Observers have reported both storm interfaces and older crusts from mid-December in the upper snowpack. Generally, the bonds at these interfaces have been favorable, though there's much we still don't know. If you find cracks that shoot through the snow or test slopes that slide easily, default to lower-angle slopes. A series of major storms produced flooding, mudslides, and downed trees in mid-December. Access to Washington Pass and Highway 20 west of Early Winters is currently closed due to mudslides and road crews working in the area. With limited access to the mountains, we have less information about the snowpack than usual. Travel with extra safety margins, make your own observations, and ease into new terrain slowly to account for the uncertainty. Make frequent observations using quick hand-pit tests and take extra time to assess before entering larger terrain. 

State and local resources are working diligently to reduce the impacts of destructive storms that occurred earlier this month. We can help by respecting affected communities, complying with road closures, and adhering to ski area uphill travel policies.

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