Bollettino valanghe

Stevens Pass

Northwest Avalanche Center
Vedi sulla mappa

Pericolo valanghe

Wed
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

Expect to find recently formed slabs in the new snow. Look for signs wind transported snow and instability as you gain elevation, and approach exposed slopes. Steer around steep slopes if you notice any long shooting cracks or find stiffer wind slabs.

Problemi valanghivi

  • Wind Slabs

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

    You may be able to trigger shallow wind slab avalanches on leeward sides of ridges. Winds have been shifting from southeast to southwest over the past number of days, so you could find slabs on a variety of aspects. Winds are decreasing into Tuesday, but instabilities could linger in some areas. There is some potential for buried weak layers, see the persistent slab problem in the neighboring East Central zone. Most likely, slabs would be shallow, and you can avoid them by steering around pillows and drifts on slopes steeper than 30 degrees. You may be able to trigger avalanches easily on steep, southeast through southwest aspects where the new snow rests on slick crusts. Use caution to stay off of cornices, as they could break easily under your feet and possibly trigger an avalanche. Even in areas where wind slab avalanches aren't big enough to be a problem, a falling cornice could be enough to knock you off your feet.

Avalanche Discussion

The pass picked up about 4" of new snow by the end of Monday, and a few more could fall before Tuesday. Winds were moderate to strong and from the Southeast at the Grace Lakes site. Althought temperatures were fairly warm, winds were plenty strong enough to drift the new snow. On Sunday, observers reported about 2" of new becoming cohesive and sliding easily with warming temperatures in the afternoon. You can find 6-10" of recent snow, since the 4th, resting on old surfaces. Just to the east, the recent storms have amounted to higher snow totals near Leavenworth and Wenatchee. Many widely propagating ski triggered avalanches have occurred, with a layer of buried surface hoar being the culprit. This layer could be problematic in the eastern edge of the Stevens Pass zone.

On Saturday, Josh found small reactive cornices and very shallow wind drifting on Big Chief Mtn. There was also significant riming on trees and older snow surfaces from the past week. On Thursday, an observer just east of the zone, on Dirtyface Mountain reported 3-5" of new snow that slid easily on slick crusts. 

Regioni coperte