Observation Date
12/13/2018
Observer Name
Bruce Tremper
Region
Salt Lake » Little Cottonwood Canyon » White Pine
Location Name or Route
White Pine - Columbine Bowl and Spire
Weather
Sky
Clear
Wind Speed
Light
Weather Comments
Stunning, bluebird day with little wind and cold
Snow Characteristics
New Snow Depth
10"
New Snow Density
Medium
Snow Surface Conditions
Powder
Snow Characteristics Comments
About 10 inches of new snow--a little more up high and a little less down low. New snow was dense with lots of rimed snow and graupel--a distinct denser layer in the middle of the new snow from the high precipitation intensity and graupel. The snow had some body to it so it's just what we need in the early season to give us a good base. Total snow depth is about 130 cm and coverage is quite good, not hitting rocks for the most part. New snow was quite wind damaged at elevations above about 10,000' but in the wind and sun sheltered slopes it was quite good. The sunny aspects developed a bit of a sun crust by the end of the day even though the temperatures were quite cold. We took a couple runs on the gentler parts of Columbine bowl but not getting into the Birthday Chutes, which looked quite wind loaded. Sunny slopes were getting a bit sun crusted in the afternoon. Then we switched to the other side of the canyon and took a run on the north facing trees on the Spire. We broke trail most of the day but there were a couple other parties in the area and we were able to follow a trail for a bit on the Spire.
Red Flags
Red Flags
Heavy Snowfall
Wind Loading
Red Flags Comments
I did not notice any recent avalanches from the storm. I noticed that a couple of skiers descended the main Tri Chutes without triggering anything but most of the snow seemed to be stripped off by wind, both before the storm and during the yesterday's storm.
Avalanche Problem #1
Problem
Persistent Weak Layer
Trend
Decreasing Danger
Problem #1 Comments
Yes, there is still depth hoar in the basement on the shady aspects but it's buried fairly deep now beneath about a meter of denser snow. The weak layer seems to have settled quite a bit and it's also bridged in most places so we're not seeing many avalanches on that layer anymore. The new snow does not seem to weigh enough to reactivate that layer, at least from what I could see from our tour today. There's still many places I would not jump into.
Avalanche Problem #2
Problem
Wind Drifted Snow
Trend
Decreasing Danger
Problem #2 Comments
The wind slabs were not much of a problem today and they should settle out quickly.
Comments
I included a couple of photos of the wind damage on both the Tri Chutes and Red Baldy as viewed from the top of the Spire in the afternoon. You can see the tracks of a couple people that broke a trail up on the ridge north of the Tri Chutes and then skied the central chute partway down and switched to the northerly chute after the central chute got rocky. They did not appear to trigger any wind slabs but the wind stripped much of the snow off of those aspects both before the storm and during yesterday's snow. Of course, I had to throw in a photo of my lovely wife Susi next to the Spire just to show what a lovely day it was. No brag, just fact.
Today's Observed Danger Rating
Moderate
Tomorrows Estimated Danger Rating
Moderate
