Observation: Mill Creek Canyon

Observation Date
1/8/2019
Observer Name
Greg Gagne
Region
Salt Lake
Location Name or Route
Mill Creek Canyon
Snow Characteristics
Snow Surface Conditions
Dense Loose
Damp
Snow Characteristics Comments
HS > 1 meter above 7500'.
Avalanche Problem #1
Problem
Persistent Weak Layer
Trend
Same
Problem #1 Comments
The old snow surface prior to the Sunday/Monday storm had faceted, and now has a cohesive, 3-45 cm, strong slab on top. Would definitely still give it more time before venturing out onto anything steep.
Comments
On Sunday & Monday was finding the density inversion(s) within the storm snow to be the weakest layer. These density inversions have settled out, and now the weakest snow is the old snow surface prior to the Sunday/Monday storm. Last week's cold, clear weather faceted the snow at the surface, and then the Friday/Saturday wind event covered some of the facets. Wind and warmth helped deteriorate some of the weaknesses at the old snow surface, but the weaknesses at the surface did remain intact. Photo below shows this layer from the old snow surface
However, was unable to get clean shears at this layer, and extended columns were all ECTN in the mid-teens, just collapsing below the shovel. Am thinking this weak layer was mostly destroyed by wind/warmth.
What I did not get to observe were thinner snowpack areas where last week's cold, clear weather helped facet much of the entire snowpack. 
Today's Observed Danger Rating
Considerable
Tomorrows Estimated Danger Rating
Moderate

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