Central Sierra Nevada

Lawinenprobleme

• 

  Deep Persistent Slabs

  N

  NE

  E

  SE

  S

  SW

  W

  NW

  • Hochgebirge
  • Waldgrenze
  • Unterhalb der Waldgrenze

  Wahrscheinlichkeit

  Unlikely

  Größe

  2

  Below treeline and near treeline NW-N-NE-E aspects remain the areas of concern. The Jan 4 crust/facet persistent weak layer in these areas is slowly gaining strength but has not fully stabilized. In most below treeline locations, this weak layer is buried 1 to 2 feet below the snow surface. In some near treeline areas, this weak layer is buried up to 8 feet below the surface under wind drifted snow. Human triggered avalanches size D2 to D3 have moved down to unlikely on a regional scale, but isolated instability is still a consideration.

  A low likelihood high consequence avalanche problem is what we are working with at this time. The persistent Jan 4 crust/facet weak layer is gaining strength, but not at the same rate in all locations. We are not quite past this avalanche problem on a regional scale. Make conservative terrain and route selections in any areas where unstable snowpit test results or other signs of instability exist.

• 

  Loose Wet

  N

  NE

  E

  SE

  S

  SW

  W

  NW

  • Hochgebirge
  • Waldgrenze
  • Unterhalb der Waldgrenze

  Wahrscheinlichkeit

  Unlikely

  Größe

  1

  Light rain on snow this afternoon and tonight below 8,000' may trigger some rollerballs or very small loose wet avalanches. Avalanche size is expected at D1. Problematic consequences of being caught would come from downslope terrain hazards such as cliffs and terrain traps below.