Bollettino valanghe

East Slopes South

Northwest Avalanche Center
Vedi sulla mappa

Pericolo valanghe

Mon
Alta quota
2 · Moderato
Limite del bosco
2 · Moderato
Sotto il limite
1 · Debole
Open full map
Non aggiornato — questo bollettino è scaduto 4 years ago. Stai vedendo condizioni passate, non il bollettino in corso.

In sintesi

With continued light snow and plenty of available snow for wind transport, avalanches will be possible in stiff wind-driven snow. Steep confined gullies, ridgelines, and at the base of cliffs will be the most likely places to trigger a large avalanche. Stick to wind-sheltered areas or avoid steep slopes where you identify stiff pillow-like drifts and wind-textured surfaces.

Problemi valanghivi

  • Wind Slabs

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

    Moderately stormy weather will continue, and the east slopes may squeeze out a few more inches of snow during the day on Sunday. These recent storms buried various older weak surfaces and slick crusts. These weaker interfaces could now be up to 2ft deep. Observations from the nearby White Pass area showed preserved, buried surface hoar in some locations. In the adjacent East Central zone, reports showed avalanches running on melt-freeze crusts on southern aspects. These weak interfaces will take some time to heal and, when buried deeply by wind drifted snow, could produce large avalanches that propagate widely. Ridgelines, rocky outcrops, confined gullies, or convex slopes are spots where triggering an avalanche will be more likely. Actively blowing snow and drifts behind objects can help you identify which slopes may have fresh wind slabs. You can also use your probe or pole to feel for stiff snow layers over softer layers. Quick hand pits can show you how easily this stiffer snow will slide. Steer around steep slopes where you find evidence of sensitive wind slabs or stick to wind sheltered terrain. 

    The old crown of a recent slab avalanche in wind drifted snow in the Ahtanum Meadows area. The 1F hard slab failed on softer 4F snow below.

    East aspect, 6800 ft

    Photo: Katie Warren

Avalanche Discussion

Last Saturday, I traveled into the Ahtanum Meadows area and found approximately 7 inches of new snow over the Christmas Crust at lower elevations and nearly 2 ft at higher elevations. Since the recent snowfall, this crust is likely buried over 3-4ft deep near and above treeline. Overall, I found a favorable bond with this stout crust. However, in some locations in the eastern Cascades, this interface is beginning to weaken and will be something to monitor going forward. 

A complex snowpack exists in many areas of the eastern Cascades with weak faceted snow and surface hoar potentially buried on sheltered northern aspects, and steep southerly aspects may have a slick melt freeze crust underlying the most recent storm snow. It will be essential to monitor how the new snow reacts as you travel. Slight variations in aspect could have very different avalanche conditions. Use quick hand pits and small test slopes to observe how well the new snow bonds to underlying surfaces. If you find reg flags such as shooting cracks, collapsing, recent avalanches, or new snow that slides easily, dial back your terrain choices to low angle slope. 

If you get out into the East-South, let us know what you see by submitting a public observation. 

Regioni coperte