Lawinenlagebericht

Elkhorns

Wallowa Avalanche Center
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Lawinengefahr

Hochgebirge
2 · Mässig
Waldgrenze
1 · Gering
Unterhalb
1 · Gering
Veraltet — dieser Lagebericht ist 3 years ago abgelaufen. Du siehst vergangene Verhältnisse, nicht den aktuellen Bericht.

Kernpunkte

Generally safe avalanche conditions exist in the Northern Wallowa and Elkhorn zones today. However, small wet loose avalanches are possible on steep > 35 degree slopes on mostly south-facing terrain at low to upper elevations. Avoid steep gullies and sunny slopes in the PM. If you head to the top of the peaks, or into more complex terrain in the alpine, you may be able to find an unstable wind-loaded pocket. 

This forecast is sponsored by the Wallowa County Gamblers Snowmobile Club. 

Lawinenprobleme

  • Wind Slabs

    • Hochgebirge
    • Waldgrenze
    • Unterhalb der Waldgrenze
    Wahrscheinlichkeit
    Possible
    Größe
    1–1.5

    Pockets of unstable wind slab may still exist in the alpine. Overnight winds have been strong enough to move snow and load leeward slopes.  Reactive wind slabs are most likely on slopes facing NW-N-NE.  The effects of recent wind-loading may present as smooth hard pillows lurking below ridgelines or sub-ridges mid-slope, as cornices hanging imposingly over steep slopes, or if settled powder snow gives way to stiff punchy windboard. These are all the signs of potential wind slab. The warm temperatures compounded by the lack of significant new snow or wind are helping the wind slabs stabilize near treeline. However, danger may lurk in isolated pockets in the alpine as the winds overnight and today are strong enough to move snow and load slopes. Look for and avoid steep slopes (>35 degrees) with large overhanging cornices, smooth textured wind pillows, and/or deposition zones with convex rollovers. 

     

    (2/19/2024)

    Wind Slab at 7400 on W aspect. Size D1.5

    Photo: Wallowa Avalanche Center

  • Loose Wet

    • Hochgebirge
    • Waldgrenze
    • Unterhalb der Waldgrenze
    Wahrscheinlichkeit
    Possible
    Größe
    1

    Lack of a hard freeze at elevations below 6000' overnight and sunny conditions today will spike this problem type in the afternoon hours. Wet loose avalanches may be human-triggered on steep >35 degree south-facing terrain in the PM with daytime warming. Potential warning signs of wet loose activity include rollerballs and pinwheels cartwheeling down the slope, sinking up to your boot tops in wet snow, or getting your sled bogged down in a soupy moist mess. Recreationists in the two zones should be especially careful traveling up steep canyon gullies and drainages in the afternoon as sunny slopes take heat, become unstable, and potentially unleash a torrent of wet avalanche debris down upon you. 

    (2/21/2024)

    West Aspect at 7200' on 2/21

    Photo: Wallowa Avalanche Center

Avalanche Discussion

Warm temperatures and sunshine will quickly heat the snow surface today.  When this snow warms up or the thin melt-freeze crust that has formed on some south-facing slopes breaks down, wet loose avalanche activity will become a real possibility. These small pushy slides can carry you to places you don't want to be. Look for rollerballs and pinwheels as visual clues of wet loose avalanches. If you see these signs or start sinking into the wet snow seek lower-angle slopes or slopes without terrain traps in case you take a ride. FYI - there is still cold fluffy snow on northerly slopes at mid to upper elevations.

Pockets of unstable wind slab may still exist in the alpine. They are most likely on slopes facing NW-N-NE.  The effects of recent wind-loading may present as smooth hard pillows lurking below ridgelines or sub-ridges mid-slope, as cornices hanging imposingly over steep slopes, or if settled powder snow gives way to stiff punchy windboard. These are all the signs of potential wind slab. The warm temperatures compounded by the lack of significant new snow or wind are helping the wind slabs stabilize. However, danger may lurk in isolated pockets. Look for and avoid steep slopes (>35 degrees) with large overhanging cornices, smooth textured wind pillows, and/or deposition zones with convex rollovers. 

This is the time of year when extra caution should be given to overhanging cornices. As temperatures rise and the sun's power grows more intense cornice fall becomes an elevated hazard. Give cornice edges wide berth, and when traveling on ridges, always stay on the windward side where signs of terra firma exist - a tree, a rock, - something to let you know your not dangling in space and tempting fate. 

For future reference: We've had over 72 hours of light winds in the alpine. Calm conditions combined with clear cold nights have produced some amazingly large surface hoar crystals on W-N-E aspects well up into the alpine. As we start to get snow on Sunday through the start of next week, this buried layer of surface hoar could become an avalanche problem. When out touring this weekend, pay attention to where you are seeing significant surface hoar formation and tuck that little tidbit in your memory bank for future retrieval. 

The persistent slab problem is showing strong signs of being unreactive. The layers of concern are now capped by dense snow and multiple strong crusts. While it is unlikely you could trigger one of these slides, it is not impossible. Avoid shallow areas of the snowpack (< 1m/3ft) and trigger points- rocks, scoured areas, and steep convexities. 

Check out WAC professional observer, Sarah Jakober's recent report from the Northern Elkhorns. 

 

 

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