Bollettino valanghe

Mt Hood

Northwest Avalanche Center
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Pericolo valanghe

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

In sintesi

New snow and strong winds will bring an uptick in avalanche danger across wind-loaded terrain. Look for conditions to become more dangerous as you climb above 6000 ft, where slabs will be denser. Simplify your terrain once you climb into the wind zone and don’t ignore obvious clues like shooting cracks or recent avalanches. 

Problemi valanghivi

  • Wind Slabs

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

    Reactive slabs of wind-drifted snow will form as new snow piles up and is easily blown by strong W/SW winds. These slabs will be most prevalent on the downwind sides of ridges, below cornices and cliffbands, and on mid-slope rollovers. These slabs may range from soft near treeline to stiffer and more consequential in alpine terrain.

    Your best tool to manage your exposure to this problem will be visual clues. Look for blowing snow, sharp cornice formation, and dune-like drifts to help you identify where the wind has built slabs. As you move around, you can use small test slopes to help you gauge slab reactivity.

    Steer around steep wind-loaded features, especially above 6000 ft, where slabs could pack a bigger punch. Shooting cracks or recent avalanches are great reasons to pump the brakes and stick to lower-angled terrain.

    Additional Discussion:

    Triggering avalanches in more sheltered terrain may become possible if you find over 6-8 inches of new snow. If this occurs, look for storm snow instabilities before engaging with steep slopes over 35 degrees. 

    (2/17/2025)

    Pay attention to blowing snow and sharp drifts like this to help you pinpoint where slabs have formed. 

    Photo: Joe Dellaporta

Avalanche Discussion

A pattern shift should bring a welcome change to snowier, cooler weather these next days. Snow levels will continue to fall through Wednesday. High cloud cover may dissipate later in the day, especially further east on Mt. Hood, which may set the stage for wet avalanche activity on sun -exposed slopes, depending on how much new snow we receive. Keep these on your radar if the sun pokes out, and avoid steep southerly slopes of consequence if you notice rollerballs releasing or deep boot penetrations in wet snow. 

We have limited information regarding potential persistent weak layers on the north and east sides of the zone. Earlier last week, I found weak structure just above Tilly Jane (observation here), and observations in the same area have since found improving strength. There was also one very large, wide avalanche reported on the Sunshine Route that likely broke during the natural avalanche cycle on the 24th (avalanche observation here). We’re not sure what this avalanche failed on, but these few observations should help you pause and dig before engaging in steep terrain in more far-flung areas further east or north around Mt. Hood.  These weak layers have led to numerous large avalanches just to our north and is listed as a persistent slab avalanche problem.

Regioni coperte