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Observation: Emma Ridges

Observation Date
1/11/2024
Observer Name
CBrown
Region
Salt Lake » Little Cottonwood Canyon » Emma Ridges
Location Name or Route
LCC, Emma’s/Culps
Weather
Sky
Obscured
Precipitation
Light Snowfall
Wind Direction
Northwest
Wind Speed
Light
Weather Comments
Afternoon only, s1-s2, light to moderate winds, moderate blowing snow. Cold single digit temps.
Snow Characteristics
New Snow Depth
5"
New Snow Density
Low
Snow Surface Conditions
Powder
Snow Characteristics Comments
60-75cm of new snow since Tuesday is my estimate( at least down to the old, hard MF crust). A few density changes in the new snow.
Red Flags
Red Flags
Heavy Snowfall
Wind Loading
Cracking
Collapsing
Poor Snowpack Structure
Red Flags Comments
The signs are there. Obs today mostly from SW-S-SE 8,700-10,200, with a peek at part of the silver fork headwall. Plenty of large collapsing when getting off the old buried skin track. Cracking in the new snow. At places I found a very thin crust down just above the primary firm MF that may have provided some of the connectivity for the collapsing (or maybe it’s just the soft 60cm storm/wind slab). Quick pit 9,900’ SW, HS 130-140cm, HST 75cm, ECTN 22 down 40cm on density change, prying block failed just above the hard MF, the layer that would be below the inconsistent thin crust (1-2cm layer possibly slightly faceted). Did not look deeper than the firm MF down 60-75cm. The area of the silver fork headwall observed had not avalanched yet.
Avalanche Problem #1
Problem
Persistent Weak Layer
Trend
Increasing Danger
Problem #1 Comments
Whether it's a storm slab, a wind slab it's sitting on one or multiple PWL's. We have all the ingredients now for large slab avalanches on one of these buried weak layers (slab, lots of new snow, wind). Over the past week or so I've seen at least 2 FCsf layers in the upper snowpack in LCC in addition to multiple places I've found buried/preserved SH (avalanches at 30* can be common on SH). Bcc/millcreek &pc ridge pack seems simpler and weaker. Shallow w/ basal FC, a faceted slab and FCsf or SH. I'd expect to see activity in these areas first but also expect to see PSlab avalanches in the deeper core areas as well
Avalanche Problem #2
Problem
New Snow
Trend
Increasing Danger
Problem #2 Comments
New snow (dry loose and storm slab) as well as wind slab in all aspects upper and mid elev and likely low elevations.
Today's Observed Danger Rating
None
Tomorrows Estimated Danger Rating
High
Coordinates