Galena Summit & Eastern Mtns

Avalanche problems

• 

  Persistent Slabs

  N

  NE

  E

  SE

  S

  SW

  W

  NW

  • Alpine
  • Treeline
  • Below treeline

  Likelihood

  Likely

  Size

  2–3

  Several days of heavy, dense snowfall, rain, and warm temperatures formed thick, meaty slabs on most middle and upper elevation slopes. Multiple crusts are buried in the upper 3 feet of the snowpack, providing possible failure layers for the slabs above. 

  Additionally, weak, sugary, faceted snow in the lower part of the snowpack is now buried 2-5 feet deep on W-NW-N-NE-E-SE-facing slopes at middle and upper elevations. Yesterday in the Boulders, a skier triggered a very large avalanche involving this layer. The slide broke ~1/4 mile wide and averaged 3-4' thick. You're most likely to poke this beast 1) where the snowpack is around 3 feet deep and  2) in windy and/or rocky areas where the snowpack depth is variable.  

  Assume this slab + weak layer setup exists on all slopes. You may or may not experience obvious signs of instability—like snowpack collapsing or cracks shooting out from your skis or sled—before triggering an avalanche. You may be able to trigger avalanches remotely—from flat terrain below, above, and to the sides of steep slopes.

  

• 

  Wind Slabs

  N

  NE

  E

  SE

  S

  SW

  W

  NW

  • Alpine
  • Treeline
  • Below treeline

  Likelihood

  Very Likely

  Size

  2

  Expect to find fresh wind drifts and slabs up to 2 feet thick in exposed, upper-elevation terrain. Watch for dunes or smooth pillows below ridgelines and cornices and on the sides of cross-loaded gullies. Cracks shooting out from your skis or sled are an obvious sign that you've found a wind slab. Any wind slab you trigger has the potential to trigger the much larger Persistent Slabs as the wind slab avalanche moves downslope.