Central Sierra Nevada

Avalanche problems

• 

  Wind Slabs

  N

  NE

  E

  SE

  S

  SW

  W

  NW

  • Alpine
  • Treeline
  • Below treeline

  Likelihood

  Possible

  Size

  1–2

  The winds may have affected more terrain than usual, but sheltered terrain still exists. Seeking sheltered areas can reduce your risk of triggering an avalanche and increase your chances of finding soft snow. Identify areas where wind slabs may exist using clues like smooth drifted snow, ripples on the snow surface, striped patterns across a slope, and cornices above a slope. Areas of wind-loaded snow may also be deeper and denser than non-wind-affected areas. If you choose to travel in wind-affected areas, move cautiously around any wind-loaded slopes and consider using lower-angle slopes, especially if you see any signs of unstable snow like cracking or recent avalanches. 

  Light snow today and increased winds may not change the conditions much. Dense slabs of wind-blown snow will still exist on many leeward slopes below ridges and on open slopes. Wind slabs also formed at lower elevations in some sheltered areas. It is becoming more difficult to trigger an avalanche as the wind slabs and recent storm snow consolidate. Still, an unstable wind slab may lurk in some isolated areas, especially in extreme or complex terrain like slopes above cliffs or in couloirs with more wind exposure or variation in the snowpack. Large cornices also loom above many wind-loaded slopes, and those remain fragile. A large cornice failure could injure a person or may provide a trigger big enough to break a wind slab loose on a steep slope. Other large triggers, like multiple people on a slope, may also be more likely to trigger a wind slab avalanche.