Bulletin d’avalanche

Mt Hood

Northwest Avalanche Center
Voir sur la carte

Danger d’avalanche

Fri
Alpin
3 · Marqué
Limite forestière
3 · Marqué
Sous la limite
2 · Modéré
Open full map
Périmé — ce bulletin a expiré 6 years ago. Vous consultez des conditions passées, pas le bulletin en cours.

Points saillants

You can trigger an avalanche Thursday on slopes steeper than 35 degrees where you find wind drifted snow and on steep, unsupported slopes with more than 6 inches of new snow accumulation. Steer around cornices and the slopes directly below them as well as convex rolls and slopes above cliffs and creeks.

Problèmes avalancheux

  • Wind Slabs

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

    Strong West wind accompanies new snow Wednesday night and Thursday. Expect fresh wind slabs to form overnight and continue to thicken Thursday. Travel cautiously sticking to ridges and windward slopes. Look for evidence of wind transport such as firm and textured snow, pillow-like drifts, cornice development, and active blowing snow. Where you see these signs, avoid slopes steeper than 35 degrees with wind drifted snow. Shooting cracks as you travel are another good indication of unstable snow. Use small test slopes to evaluated the bond of wind transported snow to the snow below.

    (12/12/2020) A textured pillow-like drift of snow that was much firmer than other snow we traveled in was a good indication that a windslab existed on this slope.

  • Storm Slabs

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Possible
    Taille
    1

    You can trigger a slab avalanche where you find recent accumulations of heavier snow above lighter snow or new snow poorly bonded to rain-soaked snow from Tuesday. Storm slabs will be most likely to be found above in wind-sheltered areas with more than 6" of fresh snow. Cracking, collapsing, and whumphing sounds are clues that storm slab avalanches may exist. Identify and navigate around slopes with more than about 6" of new snow that are over 35 degrees.  Steer around convex rolls and unsupported slopes such as those above creeks and cliffs.

    (11/25/2020) Test slopes can give you a lot of good information about how new snow has set-up after or during a storm. This test slope shows that storm slabs are sensitive and propagating easily.

Avalanche Discussion

Rain and mixed precipitation made it's way up to around 7000' on Tuesday leaving a breakable crust on the surface Wednesday. Snow is just beginning to accumulate Wednesday evening and we are expecting decent accumulations for Mt Hood Wednesday night and Thursday. Temperatures are moderate with this storm and new snow should bond reasonably well to the snow below, but driving winds can quickly build wind slabs large enough to bury or injure a person. Careful route-finding and conservative terrain choice can help keep you out of harm's way.

During the ongoing Covid-19 pandemic, continue to follow the latest guidance from local, state, and federal health officials. Avoid unnecessary risks that could impact first responders and stress medical resources.  Wear a mask when appropriate, practice social distancing, and consider recreating closer to home.

Régions couvertes