Professional Observation

Observation Details

Signs of Unstable Snow

Key Points

Significant amounts of blowing snow were observed today in the Lundy area from today’s increased southwest winds. Limited time kept me from getting to the ridgeline where fresh deposits would have been more likely but judging by the blowing snow I could see I would not have been surprised to find some fresh and thin deposits in leeward catchment zones above treeline.

Some recent rollerballs were observed below treeline on the southerly-facing terrain in the main drainage as well as on an NW slope below exposed cliff bands in the Deer creek drainage. All of these seemed to have occurred sometime in the last couple of days. I did not observe any recent loose wet sluffs. Melt-freeze crusts up to 2” thick were observed on solar aspects at all elevations.

My main goal today was to try and find an area with buried facet crust combos and to evaluate the potential of this poor structure to produce an avalanche. I dug in on a NE aspect at 10600’ after identifying the presence of a buried thin crust with periodic probing. In this location, I found about 20 cm of soft unconsolidated snow above a thin (1-1.5 cm) wind board. below the wind board, I found a thin layer of 4f decomposing grains and small (.3-.5 mm) near-surface facets above a dense layer of rounding grains. Stability tests identified the base of the thin windboard as the layer of concern however there was not much of a slab in this area and my tests did not indicate a high likelihood of propagation. (CTHrp ECTnX2)