Bulletin d’avalanche

Mt Hood

Northwest Avalanche Center
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Danger d’avalanche

Sun
Alpin
3 · Marqué
Limite forestière
3 · Marqué
Sous la limite
2 · Modéré
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Périmé — ce bulletin a expiré 2 years ago. Vous consultez des conditions passées, pas le bulletin en cours.

Points saillants

New snow, strong winds, and possible weak layers in the upper snowpack will make for a heads up Saturday. You can trigger large avalanches in wind drifted snow, but don’t underestimate steep terrain on more wind sheltered slopes either. Let the storm run its course and seek out slopes less than 30 degrees for the safest travel. 

Problèmes avalancheux

  • Wind Slabs

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Likely
    Taille
    2–2.5

    Wind slabs will be large and ripe for human-triggering by Saturday morning and in some cases, they could release naturally. SW winds have been cranking and redistributing new snow along NE-E-SE aspects around Mt. Hood. Due to these high winds, don’t be surprised to find these dense slabs further down slope than usual or on mid-slope convexities. Some of these wind slabs could break in surprising ways or propagate widely if they fail on weak, faceted snow on or just below a crust. 

    These wind slabs will often lurk on the downwind side of ridges, below cornices, and in steep cliffy terrain. However, Saturday won’t be the day to sneak around wind-loaded slopes. Just consider avoiding this type of terrain altogether. You can use visual clues like blowing snow or surface clues like ripples, dunes, and pillow-like slabs to help you identify and avoid wind-loaded features. Shooting cracks and recent avalanche activity are great reasons to dial it back and seek out more sheltered terrain. 

    (1/22/2024)

    Visual clues like blowing snow and textured drifts will help you pinpoint problematic slopes. 

    Photo: Joe Dellaporta

  • Storm Slabs

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Likely
    Taille
    1–2

    We’re getting enough new snow over variable surfaces that triggering avalanches in more sheltered terrain is not out of the question. Avalanches could break within the new storm snow or at the new/old snow interface. Prior to this storm, backcountry observers reported everything from melt-freeze crusts, old wind-drifted snow, and weak-faceted grains on sheltered, northerly aspects. New snow will bond differently to these surfaces and avalanche activity may not be consistent from slope to slope. 

    Due to this variability, snowpack tests and test slopes may not paint the full picture. You’ll want to collect information from many data points during your tour and most importantly increase your margins. Avalanches could break in surprising ways if they fail on faceted grains or surface hoar, which did exist on shaded, N-E aspects, particularly at middle elevations. Saturday will be a good day to avoid any open slopes greater than 30 degrees. 

    (1/31/2025)

    An example of a storm slab avalanche from the West North zone on Friday. 

Avalanche Discussion

The January drought has ended and old man winter has finally returned. With that, be ready to take a big step back with your terrain selection. The recent dry weather was a great opportunity to climb higher or ski steeper terrain with good snowpack stability, but that is no longer the case. An impactful storm and uncertainty around recently buried weak layers are good enough reasons to take a big step back and enjoy mellow powder skiing or riding until the storm has run its course. 

This is a pretty  unique snowpack setup for our region, and we are in the midst of a standard Cascadian storm. Multiple long-time avalanche professionals have mentioned that the last time we had a similar snowpack was in 2017-2018, which resulted in 7 deaths throughout the Cascades in roughly a week. You can read the accident reports here to re-familiarize yourself. Needless to say, many professionals are on edge about how the next few weeks are going to play out. 

Let us know what you see by submitting a public observation. 

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