Bollettino valanghe

Stevens Pass

Northwest Avalanche Center
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Pericolo valanghe

Wed
Alta quota
3 · Marcato
Limite del bosco
3 · Marcato
Sotto il limite
2 · Moderato
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Non aggiornato — questo bollettino è scaduto 2 years ago. Stai vedendo condizioni passate, non il bollettino in corso.

In sintesi

We could receive 6-10 inches of snow by the end of the day Tuesday with wind, and human-triggered avalanches will be likely. Avoid all steep slopes, but especially ones where you can identify wind loading. If you see natural avalanche activity, stay more conservative and avoid terrain beneath steep slopes as well. 

Problemi valanghivi

  • Deep Persistent Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Possible
    Dimensione
    2–3

    Avalanches that run on deeply buried weak layers could be 3-4ft or deeper, and can propagate widely across the slope. You won't get signs of instability before triggering one, as the layer is too deep. Your best bet is to remain aware of the terrain around you, staying out of complex alpine terrain and off of steep, unsupported, or wind-loaded slopes.  

    The weak snowpack structure has been slow to gain strength. You can find a thin layer of softer facets over a hard crust, about 3 .5-4.5 ft below the surface. This layering (and the likelihood of triggering avalanches) is most pronounced at upper elevations (above 5,800ft) and further east in the zone. On Tuesday, a skier was buried in a large avalanche that likely ran on the early February facet/crust layer on Jim Hill. 

    (3/5/2024)

    Large deep slab off the W summit slopes of Jim Hill. NW at 6,500ft.

    Photo: Nate Hough-Snee

  • Storm Slabs

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

    We're receiving another 6-10 inches of new snow by the end of the day Tuesday. Most avalanche activity will probably be in wind-loaded areas, but if you find deeper pockets of low-density new snow, steer around these areas on steep slopes as well to give it time to settle.

    You can use small test slopes or hand pits to check for instabilities. Feel for stiffer slabs, where wind deposited snow, as these areas will likely be more reactive and should be avoided. When in doubt, avoid all slopes greater than 35°. 

    Theres a small chance that some sheltered north-facing slopes could harbor buried surface hoar beneath the new snow layer, probably less than 2ft deep. It might be hard to find because it's not in many places, but an avalanche would be easier to trigger and would surprise you by propagating deeper and wider than you'd normally expect. 

    Example of a skier triggered avalanche (size D1) about 1 foot deep in recently fallen snow. 

    Photo: Stephen Semanski

Avalanche Discussion

NWAC will be closed on Tuesday, March 12th, as we gather and grieve following the death of one of our forecasters, Matt Primomo. We will not issue regular avalanche or mountain weather forecasts on Tuesday. We will return to normal operations on Wednesday, March 13th. We appreciate the community's understanding and support during this time.

Outlook for Wednesday: The storm is winding down and stability should slowly improve. Deep persistent slab problems will remain. The sun may pop out and moisten southerly surfaces, and small amounts of wet loose avalanche activity could result. 

Forecast discussion:

Forecasts are showing almost half an inch of water overnight, which could equate to almost 6 inches of snow. A little bit less snow is expected during the day. Near the bottom of the lower elevation band, we'll probably be getting rain and snow will be moist. Small wet loose avalanches may occur. The other avalanche problems noted will be less likely in these areas. Crusts exist on south facing aspects beneath any new snow we've received in the last few days. 

Regioni coperte