Avalanche forecast

Mt Hood

Northwest Avalanche Center
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Avalanche danger

Thu
Alpine
2 · Moderate
Treeline
2 · Moderate
Below
1 · Low
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Highlights

Wind slabs will remain reactive to human trigger in areas where they are poorly bonded to the underlying crust. These avalanches are mostly small, but could be large at upper elevations. Cornices point to the steep slopes and generally east-facing aspects where the problem lingers.

Avalanche problems

  • Wind Slabs

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

    Slabs 24-48 hours old will remain reactive to human trigger where they rest on a poorly bonded early February crust. Typically wind slabs lose reactivity fairly rapidly after a storm, but with facets identified at the crust interface, we think the problem warrants continued heightened caution.  Wind slabs will be more reactive and potentially large at upper elevations.  At middle elevations, they will be smaller and easier to steer around. E winds on Sunday shifted to the SW Monday afternoon with moderate winds and strong gusts into the early morning hours on Tuesday. More reactive slabs should generally be found on the E and N sides of ridgelines, opposite slopes scoured down to the crust. Most middle elevation slopes above 6000 ft have around 4-6" of snow. Any slope with wind deposition (more than 6" of snow) should be treated as a potential slab that you can trigger on a slope steeper than 35 degrees. When in doubt, stick to scoured or wind-protected terrain and reduce your slope angle if you encounter whumphs or propagating cracks.

    Snow showers could mask wind slabs, masking them and making them harder to find. When in doubt, use a probe from the ridgelines to test a slope to see if you find firm, punchy snow and deeper snow depths on a potentially wind-loaded slope.

     

    (2/6/2024)

    Shooting crack in wind drifted snow. 

    Photo: Joe Dellaporta

Avalanche Discussion

Observers reported 4-5" of snow above the early February crust at Timberline on Tuesday morning. 4-8" slabs reacted easily to slope cuts in dense (4F) snow, sitting above facets on a crust (check out the video in the gallery). This is a classic recipe for wind slab reactivity on Mt Hood. We don't know how long this interface will take to heal, but it's more likely to heal quickly on aspects warming with a bit of February sunshine. 

 Snow lines rose to around 5000 ft by late Monday, so only 1-2" of snow exists above the February crust at lower elevations. You're likely to also find a potentially breakable crust at these elevations. The sun made an intermittent appearance, but we're not sure whether they triggered any wet loose avalanches on Tuesday.

This surface crust should limit the potential for wet loose activity at lower elevations on Tuesday, but less wind-affected middle-elevation snow surfaces could warm up and destabilize. Reduce your exposure to steep, SW-S-SE slopes experiencing direct sunshine if you find more than 4" of snow above the crust. Rollerballs and snow shedding of trees, rocks, or cliffs give you a final reminder.

The snowpack has transformed over the past week with several inches of rain and warm temperatures. Temperatures returned closer to seasonal norms, but we're left with a more variable snowpack. We lost significant snow at lower elevations, leaving us with many open creeks and shallowly buried obstacles to avoid. Fortunately, middle and upper elevations have held more snow. If you head into the mountains, travel cautiously, as you may encounter new hazards (rocks, open creeks, etc) that weren't present last week. 

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