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Observation: Mill B South

Observation Date
12/19/2020
Observer Name
CBrown
Region
Salt Lake » Big Cottonwood Canyon » Mill B South
Location Name or Route
BCC, Mill D South
Weather
Sky
Broken
Wind Direction
Northwest
Wind Speed
Light
Weather Comments
CLR-Few in the morning, increasing clouds through the day to produce BKN skies in the afternoon. Winds were blowing some snow around in the morning, calmed mid to late morning, then started increasing in the PM.
Snow Characteristics
New Snow Depth
2"
New Snow Density
Low
Snow Surface Conditions
Powder
Snow Characteristics Comments
Picked up about 2" yesterday. Storm overall around 9,500' seemed to be about 12-16"
Red Flags
Red Flags
Recent Avalanches
Wind Loading
Cracking
Collapsing
Poor Snowpack Structure
Red Flags Comments
Still plenty of collapsing today, even on previous skin track. Poor structure persists. Another quick ECT similar location as yesterday. 9,700' NE Intermediate ridge, HS 95cm, 40cm slab sitting on the 2-3cm of FCsf, ECTN2. Watched a 3 pack skin up Hansen's and above together, then trigger SS-AS-D1.5 right were you'd expect on the roll 10,000 NE. Looked to be ~60' wide ran 100-200'. Maybe better report from party involved.
Avalanche Problem #1
Problem
Persistent Weak Layer
Trend
Same
Problem #1 Comments
It persists, slightly less touchy today thean yesterday. No major change.
Avalanche Problem #2
Problem
Wind Drifted Snow
Trend
Increasing Danger
Problem #2 Comments
Came across some wind slab below the Ivory's, saw blowing snow, slabs were building and stiffening as I left, still SS.
Comments
No major change in stability. My big takeaway was watching some of the decision making going on in the drainage. Skining uphill close together in PWL terrain when things are this connected with overhead hazard are not safe travel techniques. Yesterday had plenty of remote triggers from quite a distance, being underneath large connected P. Slab's is dangerous right now. P Slab avalanches are unmanageable problems, especially when the bed surface is the rocky ground. Skiing alone in P. Slab terrain is not wise. Following skin tracks blindly is not a great idea, make decisions for yourself. Concerned that tracks attract other skiers...
Sorry for poor lighting in picture.
Picture one and two, inside the circle is 3 close proximity skiners.
Picture three is avalanche on hansen roll with skier off to the lookers right in circle
Picture four has avalanche in circle
Today's Observed Danger Rating
None
Tomorrows Estimated Danger Rating
None
Coordinates