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Observation Date
2/5/2021
Observer Name
cmackenzie
Region
Salt Lake » Big Cottonwood Canyon » Willows
Location Name or Route
Willow Heights
Weather
Sky
Overcast
Precipitation
Light Snowfall
Wind Direction
West
Wind Speed
Light
Weather Comments
S1 increasing to S2 by 1000. Winds along the PC ridgeline on the low end of moderate with gusts to mid 20s.
Snow Characteristics
New Snow Depth
2"
New Snow Density
Low
Snow Surface Conditions
Powder
Snow Characteristics Comments
Evidence of pre storm rime event on west aspects above 9k. W through SW aspects stripping with rapid loading onto E facing Monitors. Isolated collapses on sheltered slopes. Observed one ARu-D1 pocket release on due north convexity at 9500'.
Red Flags
Red Flags
Heavy Snowfall
Wind Loading
Poor Snowpack Structure
Red Flags Comments
Expecting more soft slab from the new snow and transport winds today.
Avalanche Problem #1
Problem
Persistent Weak Layer
Trend
Same
Problem #1 Comments
Found a few different persistent layers buried on various slopes.
- Most concerning was the evidence of chained depth hoar even onto due west aspect. Although it looks like some rounding is occuring in the pack, we have a consistent 1-1.5 meter slab sitting on this layer. Similar structure to what we're seeing full depth slides run on during mitigation work in the resort. We're tipping the scale to where this deep layer is becoming active with serious consequences.
- Small pockets collapsing on buried near surface facets mid pack with potential for a half meter slab by the end of this storm
Avalanche Problem #2
Problem
Wind Drifted Snow
Trend
Increasing Danger
Problem #2 Comments
Obvious transport occuring throughout the morning onto easterly aspects. Could increase depending on snow totals today.
Snow Profile
Aspect
West
Elevation
9,700'
Slope Angle
25°
Today's Observed Danger Rating
Considerable
Tomorrows Estimated Danger Rating
High
Coordinates