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

  1–2

  Slabs exist above widespread, weak layers (facets, surface hoar, crusts, and combinations). Persistent Slab avalanches are most likely in thinner snowpacks around the Wood River Valley. Before triggering an avalanche, you 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 snowpack is less than 4 feet 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

  Additional Discussion - Wind Slabs: Near Dollarhide and in the Soldiers, look for sensitive wind slabs near ridgelines and along steep mid-slope gullies. You can reduce your chances of triggering a wind slab by avoiding slopes with obvious signs of wind-loading, such as new cornice growth and large dunes or pillows of wind-blown snow. Cornices are large and may be unstable. Warming temperatures may cause overhanging cornices to sag and fail. Limit time beneath these features and give them a wide berth when traveling along ridges. 

  

• 

  Loose Wet

  N

  NE

  E

  SE

  S

  SW

  W

  NW

  • Alpin
  • Limite forestière
  • Sous la limite forestière

  Probabilité

  Possible

  Taille

  1–2

  Anticipate loose snow avalanches on very steep, rocky slopes receiving direct sun. Avalanche activity is most likely on S-facing slopes by midday and on W-facing terrain this afternoon. These slides often initiate near the base of trees and rocks, gathering snow and growing in size as they move downhill. Rollerballs, or pinwheels, signify that the snow is heating up, and wet avalanches may soon follow. 

  While most will start small, they will be plenty large enough to knock you off your feet and carry you into unwanted terrain. Even small slides are consequential above terrain traps such as gullies, creeks, and thick timber. Plan your day to avoid lingering under steep, sunny slopes.