Bollettino valanghe

East Slopes Central

Northwest Avalanche Center
Vedi sulla mappa

Pericolo valanghe

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

In sintesi

There's still a chance for wet avalanches on steep, sunny terrain, particularly in the afternoon. These avalanches should mostly be inconsequential. If you find unsupportive wet snow, move off of steep slopes and don't linger on or under steep, rocky terrain.

Problemi valanghivi

  • Loose Wet

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

    The snowpack hasn't fully transitioned to spring melt-freeze conditions at many elevations, and temperatures have been chilly for mid-April. The intense April sun can quickly warm snow surfaces, particularly in areas with previously dry snow. We expect most wet loose avalanche activity to be small. Take note that to the north, avalanche professionals on Highway 20 observed large wet avalanches on Thursday. These larger avalanches indicate that our snowpack hasn't adjusted to the spring weather, and wet avalanches could entrain a significant amount of snow as they travel, becoming large and dangerous. Move off steep slopes if you begin to sink into deep, wet snow or see steep rocks shedding snow in the sun. There may also be lingering glide avalanche potential on rock faces and steep, smooth slopes. If you see a big frowning glide crack or hanging blocks of snow on rocky ledges, give yourself a wide berth around these unpredictable avalanches. 

    (3/18/2023)

    Wet loose avalanches often initiate from steep rocky terrain like in this photo. 

    Photo: Pat Riffie

Avalanche Discussion

On Friday, Matt Primomo found a shallow and mostly transitioned wet or frozen snowpack on low-elevation east aspects of Wedge Mountain. South aspects were melting out. He found evidence of the wet avalanche cycle from the 9th. See photos below.

You may still find isolated pockets with lingering wind slabs in alpine terrain. Steep ridgelines, the base of cliffs, and confined alpine features above 6500ft are the most suspect slopes to trigger one of these avalanches. If you see large pillow-like drifts, shooting cracks, or the snow feels hollow beneath you, simply travel on lower-angle slopes or steer around these wind-loaded features. Last weekend, some wind slabs in the Mission Ridge area stepped down onto a weak layer of surface hoar formed at the end of March. While unlikely, some older wind slabs may still run on this weak snow layer. The surface hoar layer is isolated in distribution, but there is potential for a large surprising avalanche on northerly aspects. 

After last weekend's rain, cool overnight temperatures created a thick crust on most surfaces at mid and lower elevations. The recent rain and warm temperatures changed the landscape a bit, and you can expect challenging travel and lots of bare ground at lower-elevation trailheads. 

Regioni coperte