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Observation: White Pine Gulch

Observation Date
1/25/2024
Observer Name
two wills
Location Name or Route
White Pine
Weather
Sky
Overcast
Precipitation
Light Snowfall
Weather Comments
light with brief periods of moderate snowfall throughout the day. a few cm's of accumulation stacking onto the 15ish cm of soft snow on sheltered aspects. High quality snow riding.
Red Flags
Red Flags
Poor Snowpack Structure
Red Flags Comments
Most of the days I've been out this past week (mostly mid - upper elevation BCC) I've felt significant booming collapses and sometimes noted shooting cracks on a variety of aspects. Today, while walking around off trail and skiing fresh snow, no such feedback was given. However with further investigation poor snowpack structure is still apparent with our December Drought Layer lying below a hefty slab. New snow was coming in gently, no notable winds, no recent avalanches.
Avalanche Problem #1
Problem
Persistent Weak Layer
Trend
Decreasing Danger
Problem #1 Comments
We dug a two pits at about 8 and 9k, see profiles below. Danger seems to be decreasing, not necessarily very quickly but more notably at higher elevations where the slab is buried more deeply. It feels like we're on the way from considerable to a spooky moderate.
Snow Profile
Aspect
Northwest
Elevation
7,900'
Slope Angle
15°
Comments
in the 7900' pit the top 15 cm of snow was dry and skied well. Most of the rest of the pack could be made into a snowball.
in the 9000' pit the whole snowpack was dry to 65 cm. We did not dig to the ground. This is pictured below. We did not do grain ID for the second full pit, we just closely inspected the layer of concern. Pictured below are rounding facets from the DDL. Our ECT gave no results on compression but with a fairly gentle pry of the shovel the whole block had no trouble failing in these facets and propogating fully.
These pits and results seem to echo the current understanding that low elevations could hold a trickier and more reactive snowpack. The weak layer is better insulated at higher elevations but still showing undesireable structure and propogation propensity with PST. Our general observations allign with Tremper's observation from White Pine yesterday.
rounding&sintering facets on a 2mm grid. 9k central white pine
tracks coming out of boulder basin, tri chutes, birthday chutes. No recent avalanches observed
Today's Observed Danger Rating
Considerable
Tomorrows Estimated Danger Rating
None
Coordinates