Central Sierra Nevada

Problemi valanghivi

• 

  Loose Wet

  N

  NE

  E

  SE

  S

  SW

  W

  NW

  • Alta quota
  • Limite del bosco
  • Sotto il limite del bosco

  Probabilità

  Possible

  Dimensione

  1–1.5

  Rapid warming this morning will quickly melt any firm snow on sun exposed slopes. Pay attention to quickly changing snow conditions today. Once the 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.

  The weather continues to feel like late spring or even summer, with warm days and nights. Clear night skies allowed some refreezing across open slopes due to heat escaping from the snowpack (radiational cooling). These refreezes are weaker, more superficial, and more variable than those driven by below freezing air temperatures. Expect loose, unsupportable wet snow to form quickly on sun exposed slopes as the surface crust melts in the warm, sunny weather. Surface wet snow will deepen as the day progresses, with wet loose avalanches becoming possible on sun exposed slopes. The sun is currently about 10 degrees higher in the sky than it was on March 1. This change has led to an increase in snow surface melt on northerly aspects. As a result, wet loose avalanches are becoming a greater concern on sun exposed northerly aspects than they were a few weeks ago.

  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 started 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.