Avalanche forecast

East Slopes Central

Northwest Avalanche Center
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Avalanche danger

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

On Monday, you'll encounter rising avalanche danger as the day progresses. The most likely spot where you'll trigger a large, surprising avalanche will be in pockets of drifted snow at middle and upper elevations. The best strategy will be to avoid steeper slopes that appear textured and loaded until the storm has run its course. 

Avalanche problems

  • Wind Slabs

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

    Multiple avalanches have been reported in wind-drifted snow over the past two days. Some of these slabs have propagated widely and broken up to 2 feet deep in favored locations. On Monday, these wind slabs may be easy to trigger - especially as precipitation ramps up and freezing levels increase during the later afternoon and evening hours. 

    Due to the uncertainty about the reactivity of buried weak layers 1-2 ft below the snow surface, you'll want to treat any large slopes with extra respect, especially in the wind loaded areas along ridgelines and near rock and cliff bands. You can use visual clues to help you identify problematic slopes. Look for textured surfaces, fresh cornice development, and pillow-like slabs at the surface to help you identify where the wind has been at work. Pull back and default to less exposed terrain if you notice whumphing or shooting cracks under your feet or machine. 

    (1/6/2024)

    You can trigger similar avalanches on Monday.

    This skier triggered avalanche occured in a wind loaded area on a NE Aspect @ 6000 ft near Blewett Pass on Saturday. This avalanche likely stepped down into old snow from December.

    SS-AS-R2-D2-O

    Photo: Max Steed

Avalanche Discussion

Observers across the region have reported endless signs of instability over the weekend. On Saturday, backcountry travelers in the Blewett Pass area had a close call with a triggered avalanche that broke 1-2 ft deep and propagated widely. This large avalanche occurred on an NE aspect at 6000 ft in a wind loaded area and likely failed on old, faceted snow from December. On Sunday, Katie traveled near Salmon La Sac and reported a large, widely propagating avalanche on a solar aspect at 6800 ft. The bed surface is unknown but likely failing on weak snow from late December. She also reported propagating tet results on buried surface hoar about 1.5 ft below the snow surface. You can check out her full observation here.  The Mission Ridge Pro Patrol reported quiet, calm conditons on Sunday - but did observe a fresh batch of surface hoar within their terrain. This will be another layer to keep track of as new snow piles up in the coming days. 

Saturday's storm brought a wide array of storm totals across the zone. The southwestern parts of the zone near Salmon Lac/ Teanaway received the most with 8-10 inches. Much less was reported at weather stations further north and east.

The snowpack in the zone is made up of a number of potential weak layers and crusts, and the upper crust isn't the only one to consider. The Solstice crust is another layer that has produced large slab avalanches with control work at Mission Ridge on December 30th. Observers reported whumphing collapses from the west side of Jolly Peak at 6,500ft on 1/3, and from 5,000ft in the Enchantments on the 28th. Though we haven't seen many avalanches on these layers yet, we just haven't had much new snow to react as a cohesive slab yet. As slabs become more connected and we add more snow, these slightly deeper layers warrant more consideration.

The snow cover is still shallow, especially further east in the zone and at lower elevations. Expect to encounter exposed creeks, and shallowly buried logs and rocks in many areas. 

If you get out, let us know what you see by submitting a public observation!

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