Bollettino valanghe

East Slopes South

Northwest Avalanche Center
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Pericolo valanghe

Sun
Alta quota
3 · Marcato
Limite del bosco
3 · Marcato
Sotto il limite
1 · Debole
Non aggiornato — questo bollettino è scaduto 6 months ago. Stai vedendo condizioni passate, non il bollettino in corso.

In sintesi

Don't be fooled by calm, blue skies. Complex and atypical weak layers within the snowpack are being tested by sizeable weather events, including recent wind loading and rapid warming. Triggering small sluffs of loose wet snow will also become possible as the day progresses. Stick to shaded, wind-sheltered terrain and slopes under 35 degrees.

Problemi valanghivi

  • Persistent Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Likely
    Dimensione
    1–2

    Poor snowpack structure exists on all aspects at middle and upper elevations. This includes layers of buried surface hoar and facets around a crust. Recent strong-extreme winds from the west may have overloaded these weak layers, and the zone will now experience rapid warming on Saturday. 

    This is an atypical snowpack setup that we don't often experience in the WA Cascades, so you can't roll out your typical playbook to recreate with. All steep open terrain is suspect, including moderately treed areas where strong wind has snuck its way in. Avalanches could be triggered from below or next to steep slopes. A change to denser feeling snow underneath your equipment is a good indication that it has been influenced by the wind. Cracking, collapsing, and recent avalanches are also a red flag indication to stay off steep slopes.

    We have uncertainty around this problem due to a lack of observations, so take some time to poke around for more info in the specific area you plan to recreate. You can dig small hand pits and pull on blocks of snow to see how easily overlaying slabs break free from weak snow underneath. Small, steep test slopes or convex features can help gauge the reactivity of the upper snowpack. But given snowpack variability, be cautious about extrapolating your results too broadly. 

    It might be more likely to trigger smaller fresh wind slabs independent of buried weak layers. However, the potential consequences of being caught and carried are the same. You should be concerned about triggering true wind slab avalanches in the same places where you could trigger a larger persistent slab avalanche. 

    (2/22/2026)

    A small, remotely triggered avalanche in the Buillon Basin area, failing 14-16" deep on buried surface hoar.

    Photo: Sam Clairmont

  • Loose Wet

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Possible
    Dimensione
    1–1.5

    This weekend is a return to warm, warm weather, although the East South zone might get a bit of high cloud coverage on Saturday. If you notice that you're beginning to sink into moistened snow, or you see fresh rollerballs falling down from cliff bands or your own equipment, mark that as a sign that this problem is turning on. Although avalanches will be small, there are plenty of exposed hazards in the terrain right now that you could be carried over, especially on southerly slopes. Lower elevation terrain, by and large, still does not have enough snow for this problem to be more than unlikely. This warming trend could even play a role in the release of a dry wind or persistent slab avalanche; however, these mechanics are not well understood.

    (2/5/2026)

    Wet loose slides on a sun-exposed slope originating in steep, rocky terrain. 

    Photo: Andy Harrington

Avalanche Discussion

Although none of the recent avalanche activity reported to us comes from the East South zone, we know similar snowpack structure exists. This includes surface hoar buried on 2/13, and weak faceted snow buried on 2/7. Weather stations in the zone picked up 1.2 inches of snow water equivalent this week, which could equate to around 1 foot of recent snow sitting on top. Where the wind has transported snow, the depth of overlaying slabs could be double that. Some photos of distant terrain in East South confirm that the recent strong-extreme west wind definitely impacted the zone.

Persistent slabs are tricky to manage in the backcountry, even with the best information, and East South has very little of it. If you plan to travel close to a neighboring zone, consider reading their forecast to outfit your toolbelt with more information. Other zones have seen a lot of action as recently as Friday. Ultimately, this problem is likely to stick around for a while, so settle in to finding fun riding on lower angle slopes while the snowpack heals.

Recent southerly flow helped precipitation accumulate in areas further east, bringing some accessibility to struggling sno parks back online. That said, the snowpack is still thin, particularly in the trees, at lower elevations, and on southerly slopes. Creeks, holes, and logs make routes convoluted or even impassable. Give yourself time to deal with our interminable "early season" conditions, and know that some hazards may be obscured by recent snow.

It takes a village to accurately forecast avalanches and create better forecast products for the community. Please let us know what you're seeing out there.

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