Central Sierra Nevada

Avalanche problems

• 

  Wind Slabs

  N

  NE

  E

  SE

  S

  SW

  W

  NW

  • Alpine
  • Treeline
  • Below treeline

  Likelihood

  Likely

  Size

  1–2.5

  Unstable snow could exist in areas where slabs of wind drifted snow have formed below ridges, in gully features, and on open slopes.  Look for cornices, wind pillows, blowing snow, and snow surface cracking to help identify where wind slabs may be forming.  Large and fragile cornices exist above many of these wind loaded slopes and could break off with the weight of a person.  Identify areas of concern and move around or avoid these locations.  Better snow quality and reduced risk to this avalanche problem will exist in wind protected below treeline areas.        

  The recent multi-day storm is winding down today.  Most recent observations point to the storm snow in wind protected areas gaining strength, transitioning from yesterday's storm slab problem to today's wind slab problem.  While some slabs may linger in protected locations, avalanches will be likely where deeper slabs of wind drifted snow exist in near and above treeline locations.  Southwest winds have increased to strong to gale force speeds and will add to and form new wind slabs today.   

  

• 

  Loose Dry

  N

  NE

  E

  SE

  S

  SW

  W

  NW

  • Alpine
  • Treeline
  • Below treeline

  Likelihood

  Possible

  Size

  1–1.5

  Snow levels and temperatures started dropping Sunday morning and continued overnight with colder and lower density snow falling.  Dry loose sluffs of the surface storm snow is expected to occur today in steeper, mostly wind protected, areas.  These dry loose avalanches could run long distances dependent on terrain and could increase the consequences of being caught and taken into any terrain traps: such as rocks, cliffs, trees, open water, etc.