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Observation: Figure 8 Hill

Observation Date
2/4/2017
Observer Name
C Brown
Region
Salt Lake » Big Cottonwood Canyon » Brighton Perimeter » Figure 8 Hill
Location Name or Route
Twin Lakes Figure 8 Bowl
Weather
Sky
Overcast
Precipitation
Light Snowfall
Wind Direction
Southwest
Wind Speed
Light
Weather Comments
Winds continued today moving the snow around. Had some on and off light precip, little bit of graupel mixed in. About 8~10" new snow vastly improving riding conditions. Sun popped out a few times during the days, but only for minutes at a time. Skies were clearing around 15:00.
Snow Characteristics
New Snow Depth
8"
New Snow Density
Medium
Snow Surface Conditions
Powder
Dense Loose
Wind Crust
Snow Characteristics Comments

Higher density new snow with some graupel mixed in made for some pleasant riding conditions.

Red Flags
Red Flags
Recent Avalanches
Wind Loading
Cracking
Red Flags Comments
Observed some cracking in what I would describe as a storm slab. Although the winds were moving some snow around, I was seeing this in less wind affected areas. Trigered a size 1 soft storm slab avalanche while traversing to avoid some rocks entering Figure 8 Bowl. Happened on a ~37* covex roll North facing at 9,900' in a pretty protected area. Only about 6~8" deep, and about ~80' crown, but for the terrain feature a large slab. Ran maybe 200' It was pretty sensitive having just started my traverse/cut in when crack propogated ~70' in front of me. Bed surface appeared to be a rough MF crust, old snow new snow interface, would suspect there were some near crust facets as the weak layer. See pictures below
Avalanche Problem #1
Problem
New Snow
Trend
Decreasing Danger
Problem #1 Comments

New snow was forming a storm slab today, in wind effected areas observed some minor cracking in the cohesive snow. Triggered one smaller avalanche. See red flag comments.

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

Didn't really feel any wind slabs first hand today, but saw them forming along the ridge of Wolverine cirque. I would suspect these may be getting closer to an unmanageable size, especially in steep consequential terrain. With the consistent moderate winds along ridge lines and the new snow available for transport these will be a concern, especially tomorrow.

Comments

Photo's below

Graupel

Wind transport on ridges

Pictures of the storm slab avalanche

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