Ogden

Problemi valanghivi

• 

  Wind Slabs

  N

  NE

  E

  SE

  S

  SW

  W

  NW

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

  Probabilità

  Possible

  Dimensione

  2

  Strong winds over the past 72 hours have made a checkerboard of both shallow soft slabs and shallow hard slabs of wind-drifted snow.

  If the snow is pillowy or rounded, you've likely found a new drift of wind-blown snow. If the snow is hard and hollow-sounding, you likely found an old hard drift of wind-blown snow. In either case, be on the lookout for wind-drifted slopes.

  These drifts may break to the old snow surface, as many observers noted the old snow surface becoming loose and faceted from the past few days of clear and cold weather. Any wind-drifted snow avalanche can also step down to deeper weaker layers on terrain facing west to north to east at the mid and upper elevations (see PWL below).

• 

  Persistent Slabs

  N

  NE

  E

  SE

  S

  SW

  W

  NW

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

  Probabilità

  Possible

  Dimensione

  3

  Think of a slab like a rubber band. When we load our snowpack with weight, we stretch the rubber band. If we stretch it too far, it will break. Will it break today? Well, that is the question. Yes, the persistent weak layer is gaining some strength and the likelihood is decreasing slowly. However, there is a significant consequence if you get this wrong. If you trigger a persistent weak layer avalanche, it will likely be season-ending, or worse, it could kill you.

  It's just not worth it yet. I do not know one snow professional willing to ride steep, northerly-facing terrain. Continue to avoid steep, shady terrain where it's possible to trigger a persistent weak-layer avalanche.

  My recommendation is to ride southerly-facing terrain, where you won't find this weak layer in the snowpack. If you want to ride northerly-facing terrain, you need to watch your slope angle, making sure you don't ride or walk underneath terrain that is greater than 30 degrees in steepness. Avalanches can be triggered remotely (from a distance).