Central Sierra Nevada

Problèmes avalancheux

• 

  Wind Slabs

  N

  NE

  E

  SE

  S

  SW

  W

  NW

  • Alpin
  • Limite forestière
  • Sous la limite forestière

  Probabilité

  Possible

  Taille

  1.5–2

  Gale force winds were observed to drift and deposit high intensity snowfall onto avalanche terrain near ridgetops, in gullies, and on open slopes yesterday, creating a wind slab avalanche problem. Slopes that are more filled in than surrounding areas with wind drifted snow are the main areas of hazard. Most slab avalanche potential will occur in above treeline and near treeline terrain today, but could be encountered below treeline to a lesser extent due to the strength of yesterday's winds.

  Slopes below cornices or wind drifts as well as cross-loaded gullies are the main areas of concern. Consider any avalanche terrain that appears more filled in with wind drift snow than surrounding areas as suspect. Snow surface cracking and/or fresh avalanches are indications of unstable snow in the immediate area. Move cautiously around slopes that hold indications of a wind slab problem. Last night's cold air temperatures may have slowed stabilization. Consider choosing moderate slope angle, wind protected terrain below treeline as a lower risk option for today.

  

• 

  Loose Dry

  N

  NE

  E

  SE

  S

  SW

  W

  NW

  • Alpin
  • Limite forestière
  • Sous la limite forestière

  Probabilité

  Possible

  Taille

  1–1.5

  Sluffs, aka dry loose avalanches, could still be triggered today by backcountry travelers, mainly in wind protected areas. On steep slopes where new snow sits on top of a firm rain crust, some of these dry loose avalanches could be long running.

  The main concern here is being caught and carried into downslope terrain hazards such as rocks, trees, or terrain traps that increase the consequences of an otherwise small avalanche. Consider selecting slopes without down slope hazards if choosing to venture into steep terrain today.