Public Observation - Snowshed Mountain hasty pit reveals slab/weak layer

Location Name: 
Public Observation - Snowshed Mountain, Flathead Range
Flathead Range - Middle Fork Corridor
Date and time of observation: 
Sat, 03/26/2016 - 13:30
Location Map: 

Red Flags: 
Recent loading by new snow, wind, or rain
Obvious avalanche path

Observation made by: Public
Snowpit Observations
More detailed information about the snowpack: 

Toured up low-angle shelves to the 7525' summit of Snowshed.   Noted some small point releases  on  40 + degree slopes as we climbed, and observed D1 loose, wet slides on S-facing slopes above Essex Creek that probably ran on 3/25.  Saw no signs of recent natural slab avalanches on Mount Adams or any other nearby peaks, though we noted recently-built-up cornices on ridges and cross-loaded areas in the Essex Creek drainage.

Ski cut a small 35 degree N-facing test slope near the top of Snowshed with no results, but noted a slabby quality to the boot-top powder.

Dug a hasty pit at 7400' on a previously wind loaded 32 degree N-NW facing slope.

Top 30 cm was fist hardness new snow.  Below this was about 25 cm of F+ wind slab.  (More about this layer in a bit.)  From 55cm down to 80 cm the snow was generally 4 finger hardness.  Between 80cm and 85cm from the surface there was a rain crust.  Below this crust the snow was generally 1 F hardness down to the next rain crust at about  120cm.

Conducted one extended column test, but did not record the ECTN results within the top 30 or so cm.  What got our attention was ECTP 24 at 55cm.   The column slid snappily into the pit on a Q1 shear in weak snow (1mm facets) right below the recent (but covered by sucker pow) wind slab.

This re-inforced our decision ski off the summit on our ascent route on the lowest angle, most densely treed terrain available.

The skiing was excellent in  low-angle N- facing glades.  We skied some short, wind-sheltered 38 degree slopes without incident, but noted minor cracking around turns in the top 20cm.  Below about 5500' the skiing became more challenging as we produced a few bowling ball+ sized rollerballs/pinwheels on slopes at all steeper than 30 degrees.

Weather Observations
Blowing Snow: 
Cloud Cover: 
50% of the sky covered by clouds
Air temperature: 
Below Freezing
Wind Speed: 
Light (Twigs in motion)
Air temperature trend: 
Wind Direction: 
High Temp. (C): 
Low Temp. (C):