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Observation Date
12/23/2013
Observer Name
Paradis / Caplis
Region
Salt Lake » Mill Creek Canyon » Porter Fork
Location Name or Route
Porter Fork
Weather
Sky
Overcast
Precipitation
Light Snowfall
Wind Direction
North
Wind Speed
Calm
Weather Comments
At 6200' it felt quite warm when starting around 10am. At 8600' it was still damp and misting and/or snowing but felt much cooler.
Snow Characteristics
New Snow Depth
3"
New Snow Density
Medium
Snow Surface Conditions
Rain-Rime Crust
Snow Characteristics Comments

The snow skied reasonably well but did have a minor rime crust.

Red Flags
Red Flags
Poor Snowpack Structure
Red Flags Comments
We didn't observe any collapsing today. In some places your pole would sink through the supportable snow and into bottomless facets.
Avalanche Problem #1
Problem
New Snow
Problem #1 Comments

Plenty of facets sit below snow from early December setting up our familiar persistent slab problem.

Buried surface hoar in this area also provides another weak layer that is now capped by the most recent snow. This could become tomorrow's persistent slab. See the profile below for more details.

Avalanche Problem #2
Problem
New Snow
Trend
Decreasing Danger
Problem #2 Comments

We didn't push slope angles or personally observe any new snow instability but the new snow had plenty of water and it is sitting on weak existing snow. Avalanches in the new snow seemed very possible.

Snow Profile
Aspect
North
Elevation
8,600'
Slope Angle
10°
Comments

This snow pack seemed to have everything and I can't recall so many different forms in one pit. This one had rime, grauple, settled snow, rounded grains, surface hoar, and facets.

This pit was in an open area and the size of the surface hoar (6-8mm) was impressive. A photo is attached below. A photo of the depth hoar near the bottom is also attached.

In our stability tests, we both expected failure on the buried surface hoar but with more energy. Our compressive test scores were all between 13-15 but with Q2 shear quality. We did get one result in the facets after removing the surface hoar and snow above that.

Today's Observed Danger Rating
High
Tomorrows Estimated Danger Rating
Considerable
Coordinates