Central Sierra Nevada

Problèmes avalancheux

• 

  Wind Slabs

  N

  NE

  E

  SE

  S

  SW

  W

  NW

  • Alpin
  • Limite forestière
  • Sous la limite forestière

  Probabilité

  Very Likely

  Taille

  2

  Wind slabs are widespread following new snow combined with gale force SW winds. The vast majority of wind slabs exist near treeline and above treeline on NW-N-NE-E-SE aspects. Unstable wind slabs may be encountered to a more isolated extent on other aspects and below treeline due to the strength of the wind. Avalanche size is expected mostly at D2 with up to size D3 possible.

  If traveling below treeline, expect that avalanches from above may run into below treeline areas. Pre-plan for low visibility obscuring avalanche start zones overhead. Move around avalanche runout zones with a wide, conservative margin. Do not underestimate potential avalanche size and runout distance.

• 

  Loose Dry

  N

  NE

  E

  SE

  S

  SW

  W

  NW

  • Alpin
  • Limite forestière
  • Sous la limite forestière

  Probabilité

  Likely

  Taille

  1

  High intensity snowfall this morning and rising snow level today will continue to provide the ingredients for a storm slab avalanche problem.  Unstable storm slabs are likely on any wind protected aspect in below treeline to near treeline terrain. Avalanche size up to D2 is expected.

  All slopes are suspect at this time and careful, independent evaluation is necessary before making a decision to enter below treeline avalanche terrain. Expect avalanche activity today and be aware of lower angle slopes connected to steeper slopes above or to the side. Get out of existing tracks and gather data. If signs of snow surface cracking or recent avalanche activity are present, make conservative decisions and avoid avalanche terrain.