East Slopes Central

Problèmes avalancheux

• 

  Wind Slabs

  N

  NE

  E

  SE

  S

  SW

  W

  NW

  • Alpin
  • Limite forestière
  • Sous la limite forestière

  Probabilité

  Likely

  Taille

  2–2.5

  Thursday brought more snow than anticipated to the East Central zone, accompanied by strong winds. The new low-density snow drifted into sensitive wind slabs on lee aspects where you could trigger an avalanche. Identify wind-loaded features with visual clues like drifts around rocks or trees, cornice formations, and textured surfaces. Avoid steep slopes where you find these stiff, wind-drifted slabs. You may also be able to trigger storm slab avalanches on steep, sheltered slopes. With 2-3ft of recent snow, these avalanches could easily be large enough to bury, injure, or kill a person. However, more concerning is that these avalanches could step down to more deeply buried weak layers, become very large, and propagate across terrain features. 

  Look for signs of instability, such as collapsing, cracks that shoot away from you, and recent avalanches. These are all indications that you are likely to trigger an avalanche. At lower elevations with a thinner snowpack, avalanches might be smaller, but they would carry high consequences if you are dragged through terrain still riddled with rocks, stumps, creeks, and other terrain traps.

  

• 

  Persistent Slabs

  N

  NE

  E

  SE

  S

  SW

  W

  NW

  • Alpin
  • Limite forestière
  • Sous la limite forestière

  Probabilité

  Possible

  Taille

  2–3

  You could trigger a very large persistent slab avalanche on various layers now buried 2-4 feet deep. These avalanches can propagate widely around terrain features, and you may be able to trigger them from adjacent lower-angle slopes. The best way to manage this avalanche problem is simply to avoid steep open terrain and slopes connected to steep terrain above. Instead, seek out low-angle, simple terrain. Before this storm, there were close calls with avalanches on these persistent weak layers. Now, these same layers are buried much deeper and continue to produce avalanches. 

  On Wednesday, Mission Ridge Ski Patrol triggered multiple avalanches that failed on weak, faceted snow over the Solstice Crust, and a backcountry traveler near Lake Wenatchee remotely triggered a small avalanche on a steep convexity on this same layer. Buried surface hoar (1/2) was responsible for two other human-triggered avalanches before this storm. We have yet to hear about more recent avalanches on this surface hoar layer, but it could still be an issue. With both layers potentially lurking below the surface, extra caution and wide safety margins in your travel plans are warranted.