Central Cascades

Problèmes avalancheux

• 

  Wind Slabs

  N

  NE

  E

  SE

  S

  SW

  W

  NW

  • Alpin
  • Limite forestière
  • Sous la limite forestière

  Probabilité

  Likely

  Taille

  1–2

  West and southwest winds have been building wind slabs over the last several days. This trend will continue into Saturday as the region receives more cold light snow that can easily be moved by the wind. Wind drifted snow will settle into a slab that is stiffer than the layer below it, creating the ideal setup for a slab avalanche. It is important to remember that wind deposits can be many times deeper than the accumlated storm snow. In much of the terrain, avalanches will be small although there are specific pockets of terrain out there that will be capable of producing a large avalanche.  Montior the depth of wind drifted snow as you move through lee terrain below ridge tops. As you observe increased depth of wind loaded snow, expect resulting avalanches to become larger. 

  Ease into steeper terrain. Look for cornices and rough, wavy, or chalky surface texture to indicate where wind slabs have formed. If you encounter cracking in wind drifted snow, or observe recent avalanches, that is a good indication to stay off of slopes steeper than 30 degrees. 

• 

  Loose Dry

  N

  NE

  E

  SE

  S

  SW

  W

  NW

  • Alpin
  • Limite forestière
  • Sous la limite forestière

  Probabilité

  Possible

  Taille

  1–1.5

  Dry loose avalanches will be possible to trigger in steep terrain anywhere the snow is not wind affected. Most dry loose avalanches will be small, but the size will depend a lot on the terrain. Expect steep and constricted terrain to allow a little more snow to move and flush through the feature.

  Monitor changing surface conditions. If the new storm snow begins to exhibit cohesion and form a 'slab' layer this could change to a storm slab problem.