CAIC: Colorado Avalanche Information Center BC Zone Observation Report

Sunday, December 29, 2013 at 12:00 AM
Front Range





  • Snowpack Obsvervation
    • Comments: NE-E-SE below treeline
      Average snowpack depth was 100 cm. In most places, upper portion of old snowpack was 4F and supportable. On very steep slopes, old snowpack was shallow and faceted, and full-depth loose avalanches were easy to trigger.
  • Snowpack Obsvervation
    • Cracking: Shooting
    • Collapsing: Rumbling
    • Persistent Weak Layer: Yes
    • Comments: NE-E-SE-E near treeline
      Intense wind loading near treeline. In the morning, slabs were 4F and 30 to 60 cm thick. Four hours later in the same location, slabs had stiffened to 1F without changing thickness. All wind slabs are sitting on low density storm snow. Wind slabs were very touchy, but would not avalanche very far on slopes less than 35 degrees.

      Below the storm snow, the old snowpack interface is either very slick, P to K-hard old wind slabs or a layer of near surface facets on top of 4F to 1F hard wind slabs. This could make for a very piece-meal, variable PWL once the storm snow settles.

      The old snowpack stratigraphy was basically one slab, ranging from 4F to K as above, and depth hoar. Typical of such a windy spot, snowpack depth and layer thickness varied considerably based on local wind patterns. HS ranged from 0 to 200 cm. Got some isolated, rumbling collapses in the depth hoar. Found one slope that collapsed naturally, but was not steep enough to avalanche. Followed cracks to the ground for over 100 meters, and it looked like they continued for another 100.


  Date Location/Path # Elev Asp Type Trig SizeR SizeD
View  2013/12/29   East Portal   3   TL   E   SS   N   R1   D1.5 
View  2013/12/29  †  East Portal   1   >TL   SE   SS   N   R2   D2