Weather
Clear, calm, cold night/warm day temperature swings.
Snowpack
I ended up digging on the avalanche bed surface, at the crown, and on a nearby slope that did not slide. I found about 35 cm of settled storm snow sitting above a wind slab layer from the mid-November wind event, above a snowpack that continues to facet. The avalanche failed beneath a Knife-hard wind slab on 1.5mm facets. The bed surface consists of a thin 1 Finger layer that is supportable to skis, but not to boots. Beneath this is about 60 cm of 1.5mm facets. All surfaces are covered with 1-2cm of near-surface facets. A nearby slope that did not avalanche consisted of a patchwork of different thicknesses and hardness of buried wind slab from 10cm Knife hard to a 4-6cm pencil hard layer. I dug in an area with a weaker wind slab layer and received moderate failures during compression tests below the wind slab and hard non-propagating failures during ECTs above the wind slab. There are two layers of concern. One above and one below the buried wind slab. Failures on the November 25th interface are trending down in likelihood and failing to propagate. Failures on the lower layer may be trending more stubborn, but the hard over weak setup is here for a while longer.
Avalanche
The observed avalanche failed far beneath the ridgeline almost midslope. Many below, near, and above treeline avalanches ranging from D1 to D2.5 observed in the basin (northwest to north through east).