Avalanche

Rock Mountain

Matt PrimomoStevens Pass
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Observation photo 1Observation photo 2Observation photo 3

Quick report

Cracking
specific

We saw quite a few natural avalanches, and there wasn't even a foot of new snow yet. With weak snow both above and below a smooth crust and sometimes to the ground, the current snowpack brings all the ingredients, and then some spicy ones for slab avalanche conditions. 

Reactive to touchy instabilities with shallow storm slabs on a slick crust, sometimes with surface hoar. Continued snow and moderate winds in the afternoon increased the slab sensitivity.

Weather

Recent Snowfall
8"

Light to moderate snow with short breaks during the day. Westerly winds were mostly calm to light early. After 1pm the wind and snowfall rates increased to mod/with stronger gusts and about 1"/hr.

Snowpack

The snowpack begins at around 4,000ft and we started skinning at 4,500ft. We found 80cm at a profile site on a SE aspect at 5,900ft. The snowpack was made up of some new, low density snow, a slick crust sometimes with surface hoar on top, facets beneath this crust, and generally smaller more resistant faceting rounds below.

We checked out the crown from a small natural on a northerly aspect at 6,300ft. The slide ran on weak snow over a very slick, thin and decomposing crust. Very weak 2mm faceted grains were beneath this to the ground, resembling a sandbox. I punched through to rocks in waist deep facets.

Avalanche

Size
D1
Count
2
Aspect
E
Trigger
N
Elevation
5400 ft

Many small slabs observed, all running on the recently buried crust. We also observed a handful of small point releases on our way down.