Valanga

Rock Creek - Wet Surfaces and Improving Persistent Problems

Clancy NelsonEastside Region
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Quick report

No direct signs of instability on the persistent weak layers, which is a big improvement for this drainage. Saw a few natural rollers and I could trigger big ones on east and west-facing slopes below treeline.

Weather

Air Temp
40s
Cloud Cover
few
Wind Loading
none
Snow Avail For Transport
moderate amounts

Another stellar Sierra day with decreasing clouds and calm winds.

Snowpack

The persistent weak layer in this area, on northeast-facing slopes, was generally between 100 and 120 cm below the surface.

The top 5 inches of snow was getting wet atop soft dry snow underneath on west to south to east-facing slopes near and below treeline. I took surface and -20cm below the surface temps 4 times: the surface everywhere and everytime was at melting point. T-20 was always below freezing. In some cases, well below freezing. The surface had refrozen into a thin, breakable crust as soon as these slopes stopped seeing direct sun.

The upper layer of the snowpack is starting to facet in the most sheltered areas that face north.

I dug a hasty pit in a below treeline area where I got widespread feedback and propagating test results on the persistent slab structure on the 8th. Today, no feedback and no results.

I also dug on the same aspect at treeline and got results that demonstrate the weak layer's ability to propagate a fracture if you can trigger it.

Avalanche

No recent avalanches.