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Observation: Snowbird periphery

Observation Date
12/17/2016
Observer Name
B
Region
Salt Lake » Little Cottonwood Canyon » Snowbird periphery
Location Name or Route
Snowbird Perimeter
Weather
Sky
Broken
Precipitation
Light Snowfall
Wind Direction
Southwest
Wind Speed
Light
Weather Comments
Totally Obscurred in the am with clearing in the pm with Broken Skies. Bitter cold and regardless of the sun coming out in the pm, all aspects obviously held up and did not crust due to the low angle sun and cold temps. Light WNW Winds with no Transport and or Wind Blown observed.
Snow Characteristics
New Snow Depth
16"
New Snow Density
Low
Snow Surface Conditions
Powder
Snow Characteristics Comments

Total Right Side Up Storm with the initial phase dropping Wet Snow and Rain up to at least 8000 feet. Below 8500 Rain Crust 3.5 cm thick and Knife Hard. CTM Scores indicated various Shears in the upper 40 cm, and ECTN with associated same Weaknesses. Thin Wind Slabs noted as well with Light Density Snow sandwiching this 1 finger slab and again No Propagation Noted. MId Pack Shears similar. Buried NSF's appear to be showing signs of rounding, and this may be associated with the Warm Temperatures and abundant Wet Snow and or Rain. 5 cm of Rounding Basal Facets observed and Non-reactive. Area observed was not in the associated Heavily Wind Loaded areas from the latest event.

Red Flags
Red Flags
Recent Avalanches
Poor Snowpack Structure
Red Flags Comments
Recent activity as noted in South Monitor causes concern for Hard Slab Potential, yet it appears that the Warm Temperatures followed by the frigid temperatures may have at least temporarily locked up some of these issues. Regardless, both Mid Pack facets and lingering Basal Facets in the Upper Elevation Northerly Facing Terrain still unproven to be safe and stable on steep terrain.
Avalanche Problem #1
Problem
New Snow
Trend
Decreasing Danger
Problem #1 Comments

Only problem noted today was the top 13 cm of Light Density Snow that showed signs of easy Sluffing in Steep terrain. Shears at 19 cm may remain active in similar terrain. Sluffing in the upper layers may continue, but with the lack of propensity to propagate other Weak Layers Noted may be adjusting.

Avalanche Problem #2
Problem
Wind Drifted Snow
Trend
Decreasing Danger
Problem #2 Comments

Lingering Wind Slabs should be settling out but with the possibility of combining this Problem with buried NSF's there may be places where Hard Slab Potential could be triggered in Shallow Locations in these Slab Structures. These may be most likely to be found on Steep Upper Elevation Northerly Facing slopes.

Moderate Danger appeared to be likely choice for the areas traveled today, yet High Elevation Wind Loaded Terrain was avoided.

Today's Observed Danger Rating
Moderate
Tomorrows Estimated Danger Rating
Moderate