Central Sierra Nevada

Avalanche problems

• 

  Wind Slabs

  N

  NE

  E

  SE

  S

  SW

  W

  NW

  • Alpine
  • Treeline
  • Below treeline

  Likelihood

  Likely

  Size

  2

  Strong S/SW winds will continue to build wind slabs in near and above treeline terrain today.  Warming temperatures with additional heavy snow will further overload these wind slabs with the previous lighter snow underneath.  Wind slab avalanches could be naturally or human triggered and could be large and destructive in size.  Look for signs of current and previous wind loading including: blowing snow, cornice formation, wind pillows, and snow surface scouring.  Make a plan to avoid wind loaded terrain and areas below large cornices. 

• 

  Loose Dry

  N

  NE

  E

  SE

  S

  SW

  W

  NW

  • Alpine
  • Treeline
  • Below treeline

  Likelihood

  Possible

  Size

  1

  Storm slabs will be possible on all aspects in wind protected below treeline areas as the storm continues.  Warming temperatures today will lead to an upside down snowpack with heavier snow on top of lighter snow.  In addition, rising snow levels throughout the day could cause storm slabs to fail with rain on new snow.  These storm slabs could be dry or wet depending on elevation and location.  Snow level is forecasted to rise to 7500' today.   

• 

  Loose Wet

  N

  NE

  E

  SE

  S

  SW

  W

  NW

  • Alpine
  • Treeline
  • Below treeline

  Likelihood

  Likely

  Size

  1

  Loose wet avalanches will be likely at lower elevations that saw snow overnight and transitioned to rain today.  Most of these loose wet avalanches should be small in size and in the form of roller balls.  Snow coverage at lower elevations remains thin and extra caution should be used to avoid all the obstacles that are hiding under the recent snow.