Sawtooth & Western Smoky Mtns

Problemas de aludes

• 

  Wind Slabs

  N

  NE

  E

  SE

  S

  SW

  W

  NW

  • Alta montaña
  • Límite del bosque
  • Bajo el límite del bosque

  Probabilidad

  Certain

  Tamaño

  1.5–2.5

  Expect to trigger 1-4 foot thick slabs in wind-loaded terrain. Some avalanches will release naturallly, and cornices could fail and trigger slabs on the slopes below.  Avalanches could be wider than you expect, and very easy to trigger, due to persistent weak layers (facets and crust + facet combinations) buried below the slabs on many slopes that face the northern half of the compass. You could remotely trigger an avalanche from lower-angled terrain above, below, or to the side of a steep slope.

  Expect to find slabs near and below ridgelines, on the sides of cross-loaded gullies, on aprons beneath chutes, and in bowls and cirques below large cliff faces in the craggy Sawtooth Mtns. The wind slabs will be most widespread at upper elevations but will also exist in middle elevation terrain. 

  Wind-drifted snow will feel stiff and may keep you on the surface. Watch for dunes, drifts, and snow pillows. Cracks shooting out from your skis or boards are a clear sign you've found a wind slab. 

  The size and chance of avalanches will increase as the day progresses. The slope you safely played on in the morning may not be safe later today. The prudent move is to steer clear of large, wind-exposed avalanche paths, including the runouts where avalanche debris would end up. 

  

• 

  Storm Slabs

  N

  NE

  E

  SE

  S

  SW

  W

  NW

  • Alta montaña
  • Límite del bosque
  • Bajo el límite del bosque

  Probabilidad

  Likely

  Tamaño

  1–2

  In areas more sheltered from the wind, the chance of slab and loose snow avalanches will increase as the storm progresses. These avalanches are most likely on slopes steeper than about 35 degrees.

  The storm snow sits atop facets,  facet + crust combinations, and crusts, depending on aspect and elevation. Slabs and sluffs will be easier to trigger in some areas than others, and the differences in stability between aspects may not be easy to recognize. 

  A kiss of wind, mild temperatures, or a little drizzle or rain is all it takes to consolidate the storm snow into a touchy slab. Although smaller than the thicker wind slabs described above, this problem could be tricky to manage. Slabs may release in surprising ways and break wider than expected. They may be triggered from a distance—above, below, or to the sides of steep slopes. It will be hard to predict which slopes are becoming unstable as the storm progresses, so build a wide safety margin to handle the uncertainty. 

  Expect heavy sluffing on many steep slopes. Triggered slides of any form may quickly gain mass and speed as they move downslope on hard crusts.