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Observation: Broads Fork

Observation Date
12/27/2019
Observer Name
Meisenheimer
Region
Salt Lake » Big Cottonwood Canyon » Broads Fork
Location Name or Route
Broads Fork
Weather
Sky
Scattered
Weather Comments
Clear, cold and calm this morning. By the afternoon the fog bank rolled in and the light became flat. No Wind.
Snow Characteristics
New Snow Depth
10"
New Snow Density
Low
Snow Surface Conditions
Powder
Dense Loose
Faceted Loose
Snow Characteristics Comments
The snow surface was FM 100 (easy listening) with surface hoar everywhere. Overall, coverage was about a meter deep (3 feet) in the sheltered trees. I didn't make it above about 8,800' in elevation so I cannot comment on snow depths higher up.
Red Flags
Red Flags
Recent Avalanches
Red Flags Comments
I did see one new snow avalanche on a steep NE facing slope at 8,800'. This avalanche was about 10" deep and 100' wide. Failing within the new snow. The slope was a wind loaded feature and had a slope angle of 40°. Other than this avalanche I saw no signs of unstable snow.
Avalanche Problem #1
Problem
New Snow
Problem #1 Comments
The new snow seemed to be the issue. In areas that formed a crust the new snow would move on top and produce fast moving sloughs. One layer I found was a graupel layer about 12-15" down in the snowpack that was fist hardness with a 12" four finger slab on top. This layer produced no results in the snowpit tests. Extended Column Test no propagation (ECTX).
Snow Profile
Aspect
North
Elevation
8,200'
Slope Angle
20°
Comments
I decided to dig my first pit on a north facing slope at 8,200' in elevation. I was quite surprised to find a very stable snowpack at this elevation. This is exactly what we want to see - lighter snow on the surface followed by harder and harder snow as we move down to the ground. There was one layer of concern (graupel) down about 12-15" but this layer produced no results in stability tests.
Just a little higher in elevation (8,500') on a northerly facing slope I was able to find weak faceted snow at the base of the snowpack. Here, the weak layer was only 2-5" thick and very wet and damp ( I will be the first to admit - I don't know what that means) but it's better than it being dry and fist hardness with faceted snow pouring out of the wall. I did an Extended Column Test and it revealed no propagation as well.
Tomorrow - I will be going back to the same area to get higher in elevation to see what is present above 9,000'.
Overall - I found a low avalanche danger on slopes facing north below about 8,800' in Broads Fork. After, digging in multiple locations and doing my homework we decided to ride steep aspects that faced the north half of the compass. Today was the first north facing slope over 36° in steepness that I've skied this season. I would follow the same conservative approach on slopes that are higher in elevation and more suspect for old weak snow. Even though I found stable snow, we still skied one at a time and had clear communication on a plan in case we were wrong.
Great Skiing!
Today's Observed Danger Rating
Low
Tomorrows Estimated Danger Rating
None