Professional Observation

Observation Details

Signs of Unstable Snow

Snow Stability

Bottom Line

The Northern Elkhorns above 7,000' received about 25cm of new snow during the recent storm. This new snow is sitting on about 5cm of partially faceted decomposing precipitation particles, which rest on the slick rain crust from 1/12. Test results were inconclusive. Small column tests indicated sensitivity to initiation (CT-M's, SP), but large column tests (ECTN's) exhibited lack of propensity for propagation.

The new/old interface is problematic with poor structure. We did get some whoomphing on several low angle slopes we traversed. The inconclusive results could indicate the new snow hasn't yet stiffened enough to exhibit slab-like properties. There could be conditions out there where the new snow could be dense enough to be more reactive, especially where the new snow was transported and deposited as stiffer windslab with the recent strong winds. Another thing to consider is...time. As the new snow consolidates and gains strength over the next few days it could start to behave as a more cohesive slab capable of propagating fractures. Due to the uncertainty of reactivity confidence is low. Best remedy...keep slope angles low.