Bollettino valanghe

Mt Hood

Northwest Avalanche Center
Vedi sulla mappa

Pericolo valanghe

Sat
Alta quota
2 · Moderato
Limite del bosco
2 · Moderato
Sotto il limite
2 · Moderato
Open full map
Non aggiornato — questo bollettino è scaduto 6 months ago. Stai vedendo condizioni passate, non il bollettino in corso.

In sintesi

Heavily wind-affected snow harbors slabs that will be stubborn to trigger on Friday. Steer around steep or poorly supported slopes in wind loaded areas, especially below large and sensitive cornices. Warming temperatures and rainfall increase the risk for generally small, entraining wet avalanches.

Problemi valanghivi

  • Wind Slabs

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

    Light amounts of new snow and modest wind transport will prevent 1-2 day old hard slabs from healing very much, and they could be large. The past few days have built large and sensitive cornices. You or a cornice failure could set off a potentially large wind slab. You might also find slabs farther down slope than you expect. Limit your exposure to the slopes below large, delicate, over-exteneded cornices where the largest wind deposits likely eist. But also be aware of mid-slope rollovers and down-canyon moraines with terrain traps that you could get you into trouble far below ridgelines. Blowing snow, smooth pillow-like drifts, and wind-stippled snow are all warning signs that wind slabs exist or continue to build in your terrain. Shooting cracks serve as a reminder that you would likely trigger an avalanche on a steep slope nearby. Early in the day, you might find isolated pockets of reactive wind slab even at lower elevations.

    (3/5/2026)

    Rippled snow surfaces and sharp drifts along a north side ridgeline. These are good clues that indicate fresh wind slabs may exist beneath the ridge. 

    Photo: Joe Dellaporta

  • Loose Wet

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

    Wet loose activity will start at lower elevations in the morning hours, expanding into middle elevation terrain in the afternoon as temperatures rise and snow changes to rain. Cold, dry, and less wind-affected snow will be more sensitive to this transition than previously wind-exposed areas. Note the change to warmer, damper conditions or active rainfall, and reduce your exposure to slopes steeper than 35 degrees, especially those above you.

    Example: A wet loose in lower White River Canyon entraining recent cold snow.

    Photo: Joe Dellaporta

Avalanche Discussion

Mt Hood picked up 6-12" of fresh snow since Wednesday morning with strong to extreme winds that gradually eased by mid-day Thursday. Areas further west in the range picked up significantly more snow, while areas further east were "snow-shaddowed " during the storm and sunnier on Thursday. The sunshine is likely to form a thin crust on sun-exposed slopes going into the next round of more modest wind and lighter precipitation on Friday.

NWAC forecasters and Mt Hood climbing rangers traveled to the NW side of Mt Hood, up to the top of the middle elevation band. They encountered stubborn, stiff slabs formed by the recent extreme W winds well bonded to an 8" thick layer of wet snow that had yet to refreeze. The recent snow was creamy on lee aspects and blasted along ridgelines. They did find a layer of buried surface hoar near the 2/13 interface, about 6" above the 2/7 crust. They did find some sudden planar results in compression tests, so it continues to be worth monitoring. The 2/7 crust has some weaker grains above it, but these are rounding and gaining strength quickly. Currently it is highly unlikely that you could trigger one of these layers, but it's not completely impossible. If you head to the north side of Mt Hood, it's worth digging around a bit and being aware of what may lurk in the middle of the snowpack. These weaknesses are limited to cold, shaded slopes and we generally believe they are on their last legs.

Regioni coperte