Wind Slab Instability
We got lucky in the Centennials with great snow and good visibility. There was about 20" of new snow from this weekend's storm. We covered 35 miles of backcountry riding and got eyes on a lot of avalanche terrain from lower elevation slopes, to Jefferson Bowl, the terrain in and above Hellroaring Creek, and East Hotel Creek. We didn't see any avalanche activity. However, we observed shooting cracks in drifts and triggered small wind-loaded slopes and cornices. So, human-triggered avalanches on wind-loaded slopes are likely.
We dug three quick pits but prioritized getting eyes on terrain over in-depth snowpack analysis:
Low-elevation slope on Sawtelle - NE @ 7600' on a slope with no wind effect: ECTX in a 160 cm deep pit
Above Hellroaring - S @ 8400' on a wind loaded slope: ECTP1 6" deep (wind slab) and ECTP21 20" deep (wind slab)
Arange - SW @ 8700' non-wind-loaded slope: ECTP21 20" deep on facets below a melt-freeze crust
Travel Advice:
- Avoid wind-loaded slopes
- While stability on non-wind-loaded slopes seemed good, it snowed a lot. So, I would either carefully assess for instability in the upper 3 feet of the snowpack with an ECT , or I would give it a few days to settle out before getting on steeper, non-wind-loaded slopes.
The danger was CONSIDERABLE on wind-loaded slopes (human-triggered avalanches likely) and MODERATE in non-wind-loaded terrain (human-triggered avalanches possible).
