Continental

Problemi valanghivi

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  Wind Slabs

  N

  NE

  E

  SE

  S

  SW

  W

  NW

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

  Probabilità

  Possible

  Dimensione

  1–1.5

  Watch out for newly formed wind slabs just below upper elevation ridgelines and on the lee side of terrain features.  There is plenty of snow available for transport and light to moderate winds have been occurring along ridgetops and wind channeled terrain.  Wind slab developement is not currently widespread, many areas remained calm yesterday and unaffected.  In areas where newly formed windslabs exist, they will likely be shallow less than 1 foot in depth.   These may have been deposited on a layer of facets that would make them more sensitive to human triggers than they typically would be.  Winds have been shifting directions over the last 48 hours.  Wind loaded slopes could exist on a variety of aspects.

   It may be difficult to discern between wind slabs that formed about a week ago and are now stable and freshly loaded slopes that could potentially be sensitive.  Older wind slabs will be much stiffer than those recently formed. Watch for signs of instability such as shooting cracks and collapsing that would indicate unstable snow.

   In areas were the snow surface is unaffected by recent wind the avalanche hazard will be low.

• 

  Glide Cracks

  • Tutte le quote

  Probabilità

  Unlikely

  Dimensione

  2.5–3

  Be aware that several glide cracks exist in our forecast area with a couple full depth releases occurring in the last week.  Most of these exist in the Maritime zone on southerly aspects of town mountain and Mile high at mid elevation.   A few others have been noted as far north as Billy Mitchell although they appear to be concentrated in the Maritime zone.  Glide avalanches are a strange beast that act differntly than other avalanche problems.  Full depth failure can occur independent of snowpack stability.  Or in other words, they can release even when a stable snowpack is in place.

  Since it is not possible to time their sensitivity the only way to mitigate this hazard is by avoidance.  First identify where glide cracks exist and avoid spending time beneath them.  Glide cracks are easy to identify.  They look like crevasses, but exist in non glaciated terrain.

  These do not produce small avalanches,  but rather failure will include the entire snowpack.