Soldier & Wood River Valley Mtns

Problèmes avalancheux

• 

  Persistent Slabs

  N

  NE

  E

  SE

  S

  SW

  W

  NW

  • Alpin
  • Limite forestière
  • Sous la limite forestière

  Probabilité

  Possible

  Taille

  2–3

  Weak, faceted snow from October exists near the base of the snowpack on many mid to upper elevation slopes facing NW-N-NE-E. Significant storms in December built a 2-3' thick slab on top of this weak layer. The problem is more common in the deeper snowpack areas of this zone, such as the Dollarhide Summit area and the Soldiers. It's been somewhat less widespread in the Wood River Valley—but you'll still find it on upper elevation, N-facing slopes. The snowpack is slowly adjusting to the load, and on wind-sheltered slopes, triggering an avalanche has become unlikely. 

  But—there's always a but—in wind-exposed, upper elevation, and alpine areas, the picture is less rosy. These places have two strikes against them. First: the wind over the past several days has continued to add more load to the buried weak layers. And second:  in this sort of terrain, shallow spots where you could impact the weak layer are more common.

  So why risk it? Safer conditions—and the best powder—can be found on wind-sheltered slopes. In these areas, the weak October snow has had more time to adjust, and you can also avoid wind slabs (Problem #2). Best to let sleeping dogs lie and take our powder hounding elsewhere!

  

• 

  Wind Slabs

  N

  NE

  E

  SE

  S

  SW

  W

  NW

  • Alpin
  • Limite forestière
  • Sous la limite forestière

  Probabilité

  Possible

  Taille

  1–2

  W to NW winds have been moving significant quantities of our light, dry snow since last Thursday. Cold, NW winds (like the past few days) are often inconsistent/erratic and tend to be directed by the terrain, and loading patterns may change from drainage to drainage.

  Observers across the forecast area reported sensitive wind drifts yesterday, and a handful of small to medium-sized natural wind slab avalanches occurred. The wind eased overnight, but many of these wind slabs will remain reactive to your weight today. Wind-affected areas can be identified by pillowed drifts or dunes, cornices along ridge crests or running down subridges, and/or stiffened snow surfaces.

  These wind slab avalanches are likely to be on the smaller side, but they could be large enough to bury you in alpine terrain where the loading has been more extensive. If you find yourself in wind-loaded terrain, you're also in an area where you're more likely to trigger a persistent slab avalanche (Problem #1 above). Steep slopes where these problems overlap are where you're most likely to get into trouble.