Central Sierra Nevada

Avalanche problems

• 

  Loose Wet

  N

  NE

  E

  SE

  S

  SW

  W

  NW

  • Alpine
  • Treeline
  • Below treeline

  Likelihood

  Possible

  Size

  1–1.5

  Daytime warming will eventually melt the firm snow surface on sun exposed slopes. Pay attention to changing snow conditions today. Once the melting snow feels wet and mushy or unsupportable, it's a good idea to opt for recreation on low angle slopes well away from avalanche terrain. Small wet snow sluffs or sinking boot-top-deep into wet snow indicate that wet loose avalanches may occur.

  Air temperatures were above freezing last night, but several degrees colder than they have been for many nights. A decent snow surface refreeze is expected to have occurred last night despite some passing clouds. As daytime warming leads to snow surface melt, expect loose, unsupportable wet snow to form on sun exposed slopes as the surface crust melts away.  Wet loose avalanches will become possible on sun exposed slopes as the day progresses. Wet loose avalanches have become a greater concern on sun exposed northerly aspects than they were a few weeks ago, now that the sun is about 10 degrees higher in the sky than it was on March 1.

  Most wet loose avalanches should remain small since repeated melt-freeze cycles and prior rain have transformed the snowpack into late spring or even summer like snow with established water drainage channels through the snowpack. An isolated, larger wet loose avalanche might occur on a long, steep slope, where what starts as a small wet loose avalanche entrains more snow as it slides downhill. Keep in mind that even small avalanches can have increased consequences in exposed terrain.