Bollettino valanghe

East Slopes South

Northwest Avalanche Center
Vedi sulla mappa

Pericolo valanghe

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

In sintesi

Avalanche hazard is slowly increasing as incremental new snow and swelling wind speeds build slabs in downwind terrain near the Cascade Crest. Shooting cracks and collapsing underneath your equipment, as well as recent slab avalanches in wind-exposed terrain should cause you to step back from slopes steeper than 35 degrees. With exposed hazards still abound, consider the consequences of being carried downslope in even a small avalanche.

Problemi valanghivi

  • Wind Slabs

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

    Increasing wind from the east will accompany another few inches of snow on Saturday. Although new snow totals aren't impressive, they will be building on a lot of low-density snow already available for transport, especially in the southern half of the zone. Most slides should be small, but they can pick up dry loose snow as they move downslope and grow larger than expected. Wind transported snow will be loading weak layers buried below, and it's not out of the question that a triggered wind slab could break more deeply or propagate more widely than expected. 

    Wind slabs typically form just below ridgelines and within concave terrain features (cross-loading). Due to easterly wind, small slabs will develop on atypical slopes. Blowing or drifting snow will be your first easily identifiable sign that slabs are being built. Also keep an eye out for other visual and tactile clues such as textured surfaces, soft, freshly formed difts/cornices, and a change to denser feeling snow beneath your equipment.

    (2/20/2026)

    Mission Ridge: Small wind slabs failed on buried surface hoar and entrained dry loose snow on the way down. These slabs were 4F+ hard and 8-10" at their deepest. Cracking can also be observed in near crust facets below the 02/07 crust. Mission patrollers reported sustained wind transport from the SW throughout the day on Friday.

    Photo: Mission Ridge Pro Patrol

Avalanche Discussion

Based on one observation from this zone and observations from surrounding zones, a complex of weak layers, including buried surface hoar and faceted snow, is present around a hard crust formed on 02/07. This crust is generally supportable to skis and possibly snowmobiles, but not boots. These layers are likely buried approximately 1-1.5 feet deep at upper elevations near the Crest in East South. On Friday in the nearby East Central zone, Mission Ridge Pro Patrol triggered small wind slabs that failed on the layer of buried surface hoar, and stepped down to near crust facets below the 02/07. The day prior, NWAC Forecasters traveling in East Central got notable snowpit test results on these layers as well.

How come we aren't forecasting for a persistent slab avalanche problem yet? The answer lies in location. On Saturday, we expect you'll only encounter slab avalanches in wind loaded terrain, which means you can treat a persistent slab problem like a wind slab problem for the time being. Where the wind is not blowing snow into more cohesive slabs, the new and recent snow is too soft and cohesionless for the right slab characteristics to develop a persistent slab problem. Regardless of where you are, you can check the bond between buried weak layers and new snow by digging small hand pits.

Speaking of soft and cohesionless, it remains feasible to trigger small sluffs of dry, loose snow in most sheltered terrain. "Manage your sluff" by slower and more deliberate travel away from terrain traps where snow will gather. You will increase the consequences of being knocked over by sluff if you travel in cliffy or rocky terrain.

Travel conditions are slowly improving, but unfortunately for the East South zone, you still won't find enough snow for on-snow recreation unless you're at Sno Parks immediately adjacent to the Cascade Crest, such as Pinegrass or Bumping Lake. Even in these parts, low coverage abound especially at lower elevations and on southerly slopes. Many other hazards, such as downed locks, rocks, random holes, and open creeks, exist at all elevations. Give yourself some extra time and take precautions when riding in these conditions. Some hazards may be obscured by new snow.

Especially with widespread weak layers buried throughout the forecast region, we need observations for this zone. Let us know what you're seeing.

Regioni coperte