Bulletin d’avalanche

Mt Hood

Northwest Avalanche Center
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Danger d’avalanche

Sun
Alpin
2 · Modéré
Limite forestière
2 · Modéré
Sous la limite
2 · Modéré
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Périmé — ce bulletin a expiré 4 years ago. Vous consultez des conditions passées, pas le bulletin en cours.

Points saillants

710 am Update: Increased to Moderate Below Treeline due to increased snow overnight.  Winter returns over the weekend and you shouldn't have to look too hard to find wind-affected snow.  Strong to extreme winds can form fresh wind slabs further downslope than usual while also stripping windward aspects.  Don't get caught out Saturday night with very cold temperatures, more snow, and persistent winds in the forecast. 

Problèmes avalancheux

  • Wind Slabs

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

    Strong winds will easily transport new snow and build firmer slabs over the latest April crust.  If you see cracking in the new snow, feel stiff or hollow snow near the surface, or see natural avalanches, these are red flags that you could trigger an avalanche on similar slopes.  There's some uncertainty about whether or not small wind slabs will develop on open slopes below treeline, so keep your tabs on conditions as you change aspects and elevations during the day.  To avoid triggering a wind slab, steer around steep open lee slopes, sticking to lower angled and wind-sheltered terrain.  

    By the end of the day, you may encounter up to a foot of new snow in some areas of the mountain below treeline.  With April showers comes the chance of graupel or soft hail.  These are additional inter-storm layers that storm slabs can fail on. Use care on very steep slopes to avoid getting surprised by a small dry loose or storm slab avalanche. 

    The weather alone will make for difficult travel at upper elevations. Commit to a safe return by knowing your route and factoring in for periods of poor visibility and cold temperatures/low wind chills if you venture above treeline Saturday.  Avalanche danger will likely increase Saturday night into Sunday with more cold snow and wind in the forecast.  

    Example of a small intentionally triggered avalanche in Salmon River in wind-drifted snow (6200ft, SE).

    The avalanche was triggered by a skier from a short distance away on the low-angled ridge. 

    Photo: Andrew Kiefer

Avalanche Discussion

Friday was a transition day as the upper mountain quickly cooled but lower and mid-elevation temperatures took their time to lower.  While winds were strong, there wasn't much new snow to work with through early Friday afternoon.  That began to change by mid-afternoon, with snow showers and strong to extreme westerly winds.  The new snow will build over the "April 8th crust".  We are not concerned about deeper layers in the snowpack heading into this storm cycle.

The weather and snow conditions this weekend will feel like a shock coming off of the Spring warmth of Thursday when 5000ft temperatures hit 60F and the strong April sun beat down on Mt Hood. Observers reported a wet and saturated snow surface, lots of rollerballs, but no significant wet loose avalanche cycle through the midweek period.  Several large or very large natural avalanches occurred early last week during a significant winter-like storm, there are several pictures in the photo reel below. 

Régions couvertes