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Observation: Shingle Mill

Observation Date
3/31/2022
Observer Name
Staples
Region
Uintas » Shingle Mill
Location Name or Route
Shingle Mill Flat
Weather
Sky
Obscured
Precipitation
Light Snowfall
Weather Comments
Cloudy, cool, with light snowfall.
Snow Characteristics
New Snow Depth
5"
New Snow Density
High
Snow Characteristics Comments
New snow from late Tuesday has settled down to 5 inches. Above 9500/10,000 on due north facing the new snow remains soft and dry. In all other places there is a melt freeze crust on top of the new snow.
Snow Profile
Aspect
Northeast
Elevation
9,900'
Slope Angle
28°
Comments
Two main questions today
1) How well did the snowpack refreeze?
2) What does the PWL faceted layer look like?
The snow was refrozen on the surface at all elevations. At the trailhead, it was a solid refreezed just on the surface, but you can still sink to your waist if you step off your sled or out of your skis when your feet break through the crust. Above 9000 feet, the snowpack is much more refrozen. Note the temperatures in the snow profile above or in the photo below.
The PWL became a little damp during recent very warm weather. It has cooled and has formed some bonds. Hand hardness increased from Fist to Four Fingers. Last week at this time my test scores ranged from ECTPV-ECTP13. Today, my test score was ECTP22. Additionally, the three ice crust above this layer will make it hard to affect this layer and trigger avalnaches on it.
Take home point - The PWL is healing and gaining strength and much harder to trigger avalanches on it. The next dramatic warm-up, could put liquid water back in this layer and make it unstable. When it refreezes again, it will be much stronger and probably no longer an issue. A more modest warm up that melts the upper ice crust could allow a person to impact this layer and trigger an avalanche on it.
Video
Photo below showing the new snow from late Tuesday that has settled to 4-5 inches.
Second photo shows runnels in south-facing terrain. These indicate that the snowpack has adjusted to the heat and the runnels give liquid water from snowmelt a pathway to travel down through the snowpack. When these form, wet avalanches are no longer a concern.
Today's Observed Danger Rating
Moderate
Tomorrows Estimated Danger Rating
Moderate
Coordinates