Summit Lake

Problemi valanghivi

• 

  Wind Slabs

  N

  NE

  E

  SE

  S

  SW

  W

  NW

  • Alta quota
  • Limite del bosco
  • Sotto il limite del bosco

  Probabilità

  Likely

  Dimensione

  1–2

  After two days of sustained strong easterly winds, we should see things calm today. That doesn't mean the avalanche problem has gone away. The most recent round of wind slabs have formed above a layer of weak snow. On some slopes this is a remarkable layer of buried surface hoar; on others it is a less noticeable layer of near-surface facets. Regardless, the wind slabs that formed over the past two days are expected to remain reactive today. The most likely places to run into this problem will be in steep terrain just below ridgelines, convex rolls, and loaded gullies above treeline.

  Look for safer conditions and better snow quality in terrain that has remained sheltered from the winds. If you see any signs like shooting cracks or collapsing, you've found the problem. Small test slopes may be an effective way of checking to see how the snow is behaving in the area you are traveling. If you are in doubt, you can play it safe by just using low-angle terrain.

  Glide avalanches: Glide cracks are still on the move, and we still don't know when they will release. These avalanches are very large and very unpredictable. The only way to manage them is to avoid spending time under open glide cracks.

  

• 

  Deep Persistent Slabs

  N

  NE

  E

  SE

  S

  SW

  W

  NW

  • Alta quota
  • Limite del bosco
  • Sotto il limite del bosco

  Probabilità

  Unlikely

  Dimensione

  2–3

  The deep slab problem is still on our radar in the Summit Lake zone. While we don't expect to see much (if any) activity on this layer, what we've seen in recent snowpits is concerning enough that we are still avoiding big terrain in the area. The layers of concern vary across the forecast zone, but they are either a layer of facets buried at the ground, or weak facted snow buried close to the bottom of the snowpack near crusts that formed in December and January. Problems like this are really hard to assess, so the way we usually manage them is by using lower-consequence terrain. This means avoiding larger start zones and steep terrain above cliffs, trees, or gullies. It may be unlikely, but we're still using terrain that reduces the consequences in the small chance that we find the place where a person can trigger one of these big avalanches.