Vail & Summit County

Snowpack

Jason Konigsberg · Dec 25, 2018 · Vail & Summit County

Weather

Mostly clear skies and warm in the sun. The southerly wind picked up in the morning moving snow onto northerly slopes. Wind loading wasn't alarming but enough to drift snow into slabs and stiffen surfaces.

Snowpack

I dug on three near-treeline slopes looking for persistent weak layers in the upper pack that may cause future problems. I found a thin, faceted layer about a foot down but it only produced propagating results on a southeast-facing slope (ECTP23). This southeast-facing slope was getting crossloaded so the upper slab was harder and stiffer than other slopes I dug on. The other slopes were northeast and east, sheltered slopes near treeeline. No results on the upper faceted layer and subtle results on the deeper weak layer 30 cm from the ground. The snowpack on these colder slopes is overall soft with few harder layers. The slab that formed post-Thanksgiving is still one-finger hard in places but is composed of faceted snow. The one-finger faceted slab over four-finger hard depth hoar is unreactive in sheltered areas. Yes, the hard over soft structure is there but the slab is "dead". This would be different on slopes near ridgetop where harder slabs have formed over the last week. I didn't test any, but Wind Slab avalanches stepping down to deeper avalanches continues to be the main concern.