Observation: White Pine

Observation Date
1/7/2021
Observer Name
McKinley Talty, Joey Manship
Region
Salt Lake » Little Cottonwood Canyon » White Pine
Location Name or Route
White Pine
Weather
Sky
Scattered
Wind Direction
West
Wind Speed
Light
Weather Comments
Skies began to clear up around noon, going from OVC to SCT. Slopes exposed to the sun after clouds parted were warming fast. Winds were calm with an occasional moderate gust from the West.
Snow Characteristics
Snow Surface Conditions
Powder
Melt-Freeze Crust
Snow Characteristics Comments
Soft snow on protected, shady northern slopes. Crusty snow surface on S and SW slopes due to yesterday's sun.
Red Flags
Red Flags
Cracking
Collapsing
Poor Snowpack Structure
Red Flags Comments
Poor snowpack structure on all slopes except due South, as expected. Isolated collapsing and cracking.
Avalanche Problem #1
Problem
Persistent Weak Layer
Trend
Same
Problem #1 Comments
We observed the faceted PWL at the base of our snowpack in all three pits dug today, as well as pole probing throughout our tour. No signs of healing, I imagine this will persist through the majority of our season.
Snow Profile
Aspect
North
Elevation
9,300'
Slope Angle
30°
Comments
Went for a tour up in White Pine today and dug three pits with my partner on mid to upper elevation N facing slopes. In all pits, we observed the PWL at the base of our snowpack with grains ranging from 1-3 mm (see photo below). Test results below:
Pit 1: NW slope @ 9100', HS=110cm. ECTP-29 @ 53cm below the surface on the faceted PWL.
Pit 2: N slope @ 9200', HS=86cm. ECTP-18 @ 46cm below the surface on the faceted PWL. PST 27/100 (End) on same layer.
Pit 3: N slope @ 9250', HS=120cm. ECTN-18 @ 35cm below the surface on a NSF layer. ECTN-23 @ 60cm below the surface on the faceted PWL. PST 30/100 (End) on faceted PWL 56cm below the surface.
While Pit 3 did not show propagation in our ECTs, we did not trust the test results and didn't let it affect our decision making. Nearly identical PST results in pits 2 and 3 show that the persistent weak layer at the base of our snowpack is more than willing to propagate and produce avalanches. We stuck to low angle terrain and found some great turns, this is not the time or season to push for bigger objectives.
Video
Today's Observed Danger Rating
Considerable
Tomorrows Estimated Danger Rating
Considerable
Coordinates