Avalanche forecast

Mt Hood

Northwest Avalanche Center
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Avalanche danger

Fri
Alpine
3 · Considerable
Treeline
3 · Considerable
Below
2 · Moderate
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Out of date — this forecast expired 6 years ago. You’re viewing past conditions, not the current bulletin.

Highlights

Significant new snow and upper elevation winds will make triggering a slab avalanche likely Thursday. Choose slopes under 35 degrees wherever you find more than 6 inches of new snow whether from new snow or wind-blown snow. Use extra caution on convex rolls and above cliffs and creeks.

Avalanche problems

  • Storm Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Likely
    Size
    1–2

    Cold temperatures should intensify the amount of new snow arriving Wednesday.  Expect significant new snow accumulations as the day wears on. With the majority of the snow falling during the daylight hours, avalanche conditions will increase throughout the day. This snow will fall on a variety of weak snow surfaces including ice, surface hoar, and faceted snow. Where you find more than 6 inches of new snow you could easily trigger soft storm slab avalanches. Watch for signs such as cracking in the snow or natural small avalanches on steep features suggesting that you could trigger a storm slab nearby. Avoid slopes over 35 degrees and steer around steep midslope terrain features and convex rolls. Use extra caution above terrain traps like cliffs and creeks that may amplify the consequence of even a small avalanche.

    (2/9/2021) New snow will fall on firm, snow with weak snow grains like the surface hoar pictured here.

  • Wind Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Likely
    Size
    1–2

    Upper elevation winds will continue to blow strongly and become more southerly during the day Thursday. Freshly wind-blown snow will accumulate rapidly on lee slopes and build fresh, easy to trigger wind slabs on lee slopes. Look for actively blowing snow, cracking in the snow, and stiff or textured snow as a sign that you can trigger a wind slab avalanche. Keep your slopes angle below 35 degree where you travel and use extra caution near cornices and ridgelines where snow will accumulate even more rapidly.

Avalanche Discussion

Strong to extreme west winds have been the main story over the last week at Mt Hood.  Strong winds were felt well below treeline over the weekend and scoured many slopes.  Tuesday and Wednesday the winds have calmed somewhat and been generally limited to the upper elevations. Despite a multi-day wind event, no new avalanches were reported since last week. Textured and firmer wind-affected snow or wind stripped ridgelines are common at all elevations.  In areas where winds have stripped recent snow, a thin freezing rain crust may glaze the surface.   An observation from Newton Canyon found this surface crust even on NE aspects below 6000 ft. In wind-sheltered areas surface snow is becoming faceted and sugary, but that is less common than firm and textured wind-affected snow or areas of scouring.

The stout mid-January crust is considered the new "ground" with a strong snowpack structure in place below this layer. Weak and faceted snow just above the stout rain crust was responsible for a number of avalanches last week, but no new evidence of avalanches on this interface suggests these facets are gaining strength. This weak layer (which is similar in structure to the fatal avalanche in WA)  still exists around Mt Hood and could produce a very large avalanche, but no evidence of recent avalanches on this layer have been reported.

Headed north to recreate?  We have a tricky snowpack with persistent slab problems in all forecast zones across the state line.  Take the time to read about the different snowpacks that have developed further north and adjust your terrain selection accordingly. 

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Preliminary avalanche incident information Monday February 8th, 2021: Two snow bike riders were caught and buried by a very large avalanche in the mountains west of Salmon la Sac Sno-Park along Cle Elum Lake. One snow biker was partially buried and was able to dig himself out. The other rider was fully buried and killed by the avalanche. The avalanche occurred on a north aspect at 4400 ft in the Knox Creek drainage. This terrain lies in NWAC’s East Central forecast zone. Avalanche classification: HS-AV-R3-D3-O. See the short video in the media gallery below.

All of us at NWAC want to extend our condolences to family, friends and the local community following this tragic event.  

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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.

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