Mt Hood

Problemas de aludes

• 

  Wind Slabs

  N

  NE

  E

  SE

  S

  SW

  W

  NW

  • Alta montaña
  • Límite del bosque
  • Bajo el límite del bosque

  Probabilidad

  Possible

  Tamaño

  1.5–2.5

  Tuesday's wind slab setup concerns us because it may be easy to trigger a shallow soft slab, but you could also trigger a deeper hard slab overlying softer snow and sitting on a crust. Intense WNW winds stripped snow off of many aspects on Mt Hood through Monday, loading multiple slopes above treeline to the breaking point. Mt Hood Meadows Patrol reported multiple small and one large natural avalanche that released with strong wind transport Sunday night into Monday morning. Other observers witnessed a large natural slab release on the upper mountain, serving as a reminder that even more dangerous conditions may exist higher on the mountain. While the potential for natural avalanches may be limited to the upper mountain, another 4-6" of snow will create reactive slabs that you can easily trigger on a wind-loaded slope steeper than 35 degrees in the morning. By the afternoon, settlement and the impact of the sun may limit these soft slab avalanches to the E and N sides of the compass. The potential for a hard slab release means that professionals would give a wide berth to large open slopes and terrain rollovers that have been wind loaded during this storm cycle. Slabs could be 5-15 ft thick and may run a long distance on the 3/21 bed surface. Cornice fall would be an easy way to trigger an avalanche on the slope below although a human trigger is not out of the question. Given the consequences, stick to smaller terrain features where you can control the scale of the problem. Avoid actively loading slopes and areas where you experience propagating cracks or pillow-like drifts. Anticipate wind loading on the E sides of canyons and wind loading may extend down to valley bottoms. If you're not sure how thick the slab may be in your terrain, seek wind-sheltered terrain (where you will find the best riding conditions) and low-angle slopes. Storm slab activity should have trended downward by Tuesday, but it's a good idea to test the snow in the upper 2 ft of the snowpack, even in wind-sheltered terrain. Winds formed slabs below treeline and in isolated areas, you may find wind drifts that you can trigger below treeline, but in general, we expect these elevations to be healing quickly by Tuesday.

  

• 

  Loose Wet

  N

  NE

  E

  SE

  S

  SW

  W

  NW

  • Alta montaña
  • Límite del bosque
  • Bajo el límite del bosque

  Probabilidad

  Possible

  Tamaño

  1–1.5

  Temperatures will be cool, but with winds decreasing and increased sunshine, expect wet loose activity to spread onto more aspects on Tuesday. These avalanches will likely be small and manageable on their own but they can pose a hazard around terrain traps like cliff bands, steep trees, or gullies.  If Monday's thin crust breaking down, rollerballs start moving downslope, or you experience wet/sticky snow it's time to adjust your aspect and limit your exposure from above. While most of these should be small, there's plenty of snow to entrain and the depth of entrainment is primarily limited by how warm the snow surface becomes.

  Don't forget about dry the potential for fast-running dry loose avalanches on cooler and shady aspects. These could take you for a ride that could end poorly in tight trees or above rocks or cliffs.