Humphreys Cirque/N. Core Ridge

It's a tale of two mountains--the West and the East.  With a predominant W. wind throughout the storm, conditions remain dramatically different depending on aspect and elevation.   In terms of the tale, the West is resembling Alaskan mid-winter alpine terrain, and the East is a forgiving snowy paradise.

Intentions for this tour were numerous:  1)  Determine the extent and sensitivity of wind slab, 2)  Determine the extent and depth of new snow coverage in the context of yesterday's 70 mph winds, 3) determine the probability of stormslab avalanches and density changes in the new snow, 4)  identify any PWLs in east facing and north facing terrain.  And of course, just checking for the usual areas of instability ;)  (Small checklist).  

Here's the take-aways:  

1.  The West is a rough-lessons schoolhouse with numerous wind and surface condition challenges.  The East, on this day, was a kind winter paradise.
2.  No signs of instability were found in the Humphreys Cirque
3.  Surface conditions in the cirque were soft shallow pow, light density snow on top of increasing density snow below
4. There were no significant PWLs in the cirque, except below the HIL, where a greenhouse of facets has sprung up
5. Return conditions to the ski area via Sundance bowl were rimed blue ice . . . better to descend in the trees left of sugar bowl
6. Scour zones remain . . .well, scoured.  HN in scour zones was 20-30 cms. 

 

Details:

West side slopes are predominately scoured with unusual wind erosion features in treed and slightly protected areas.  Winds have scoured these erosional pockets down to dirt, rock, grass, or worse yet, to the holiday ice lens.  Skinning conditions were mixed and moderate to difficult.  Winds on the ridgeline were gusting into the 30s.  Windslab below the ridgeline was stiff and unreactive. 

We dug two pits, one on a ENE slope at 11,750'.  HN 90. CT revealed one weak layer at 30 cms down from top in a storm density change, RP.  Two ECTS:   ECT resulted in an ECTN18 @ 30 cms from top, and an ECTX.

Our second pit was on a N facing slope at 11,650'.  HN 160. ETCX.  Firmer snow ranging from F to 1F.  Facet garden present below the HIL.

Skinning conditions were fast on low angle slopes and loose and a little slippery on steep slopes.  There was some potential for dry loose releases.

 

The below danger summary is for this tour only.  Danger levels in the cirque were LOW, ratings on the West were moderate with isolated pockets of potential D1 stubborn windslab.

Small pockets of instablity found in wind drifted snow on the way up to the saddle. No instability was found in the Humphreys Cirque.