Galena Summit & Eastern Mtns

Problemi valanghivi

• 

  Persistent Slabs

  N

  NE

  E

  SE

  S

  SW

  W

  NW

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

  Probabilità

  Possible

  Dimensione

  2–2.5

  Slabs that formed in early February rest above a variety of ugly, widespread, weak layers (facets, surface hoar, crusts, and combinations). Before triggering an avalanche, you may or may not experience obvious signs of instability like snowpack cracking and collapsing or whumpfing. Persistent Slabs can release in surprising ways and break much wider than expected. You are most likely to trigger a dense, 2-4 foot thick avalanche where:

  • The slab is less than about 2' thick—relatively shallower spots may exist where the wind frequently blows, and the slab is not uniformly thick.
  • Any part of the slope you are on or connected to is steeper than about 35 degrees
  • The slope faces the northern 2/3 of the compass
  • A smaller wind slab or loose snow avalanche overloads the buried weak layers (problem above)

  

• 

  Wind Slabs

  N

  NE

  E

  SE

  S

  SW

  W

  NW

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

  Probabilità

  Possible

  Dimensione

  1–2

  Recent snowfall and wind created two avalanche problems to keep on your radar:

  Wind slabs may have formed immediately beneath exposed upper elevation ridgelines and on the sides of cross-loaded gullies. The slabs could rest above weak crust/facet combinations on southerly aspects or small sugary facets on more north-facing slopes. They can be up to 2 feet thick and break wider than expected. 

  Loose snow avalanches or sluffs are possible in very steep terrain. Although most will be small, they may be large enough to knock you off your feet. Even small slides can be consequential above terrain traps such as gullies, creeks, and thick timber.