Central Cascades

Problemas de aludes

• 

  Wet Slabs

  N

  NE

  E

  SE

  S

  SW

  W

  NW

  • Alta montaña
  • Límite del bosque
  • Bajo el límite del bosque

  Probabilidad

  Likely

  Tamaño

  1–2.5

  Wet Slab avalanches occurr when rain and warm temperatures bring free water into the snow pack.  Rain adds more load to our snowpack and it also percolates down to  weak layers that maybe weren't quite weak enough to be problematic.    We have several weak layers in our snowpack right now:  previously cold dry powder from early in the storm, as well as facets that developed during the cold dry weather after Thanksgiving.  Today at 6,500 ft. these facets were failing with sudden test results 55 cm. below the surface (see accompanying video).

  Wet Slabs are  difficult to predict.  One critical factor is how deep water has moved in the snowpack.  This depth will obviously increase as steady rain continues, but it will vary over elevation as the snow line moves higher.  The forecast is calling for a decrease in rainfall, but with periods of rain and temperatures above freezing this is a hard problem to time.

• 

  Loose Wet

  N

  NE

  E

  SE

  S

  SW

  W

  NW

  • Alta montaña
  • Límite del bosque
  • Bajo el límite del bosque

  Probabilidad

  Likely

  Tamaño

  1–2

  As rain and warm temperatures melt the surface snow, Wet Loose avalanches are likely.  They should definitely be a secondary concern to the Wet Slab problem since they are significantly smaller.  Wet Slabs and Wet Loose avalanches can occurr together.