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Observation: Provo

Observation Date
12/28/2022
Observer Name
Erik F
Region
Provo
Location Name or Route
Aspen Grove
Red Flags
Red Flags
Recent Avalanches
Collapsing
Poor Snowpack Structure
Avalanche Problem #1
Problem
New Snow
Trend
Decreasing Danger
Problem #1 Comments
Approximately 30cm of new snow above 7400', 20-25cm at Aspen Grove trailhead (6900'). As best as I could tell, rain occurred up to about 7400' before transitioning to snow. Ski pen was 15cm at the location of my pit, the first 15cm of new snow from 7500-8500' is VERY dense. A fun riding medium density 15cm to top if off. A solo skier reported viewing what seemed to be a natural avalanche in the new snow in UFO Bowl #3. He was unable to get a full view of the depth, size, and length.
Avalanche Problem #2
Problem
Persistent Weak Layer
Trend
Same
Problem #2 Comments
The NFL (November facet layer) is buried by 90cm (3 feet) of new snow, rounding facets, and graupel. It was still reactive in tests (CT14 Q2 and ECTP21). I believe the danger will remain the same until the incoming snow starting Friday. Then we will experience increasing danger but with hope that enough snow buries the layer deep enough. I was able to make a snowball with the first 5-10cm of snow at the ground. Boot pen is still to ground. Is the small surface hoar/graupel mix/rounding facets beneath last week's dust event at 88cm a future PWL? I am more concerned with this layer than any other with the incoming snow as it's only 40cm below the surface. I had one collapse at 8350' on N aspects. A party reported to me that they had several collapses, one on a southerly aspect.
Snow Profile
Aspect
North
Elevation
8,400'
Comments
Lots of friendly folks out today, gotta love it! Super fun skiing, fast creamy powder. I began my tour at the Aspen Grove trailhead at 7:30, temperature was just below freezing, calm winds and S1 precipitation. Precipitation varied between S1, S-1, and NO. On the ridgeline at 8400-8600' temperatures ranged from 24-28 degrees F. Quite a bit of humidity and felt pretty warm all day. I exited at 12:00 and at the trailhead temperature was 30 degrees F. Cloud cover went from overcast, to broken, to obscured. Visibility was poor at 8400-7400' on the last descent of the day (approx. 11:40). Surprising results in the snowpit for me today. I went in thinking about the NFL but had some surprises at 42cm from surface at 88cm from ground (see snow profile). As far as I could tell, there seemed to be remnants of 2mm surface hoar and 3.5mm graupel mixed with rounding facets beneath the dust layer from last week. The NFL will (hopefully) be buried enough after this weekend as it already has a solid 3 feet on top of it. But it very well could activate during the incoming storm(s). But the weak layer at 88cm may become the more active weak layer. I'll have to get out this weekend to see what happens with the new snowfall. Another interesting result was during my ECT when I had failure and propagation at both 88cm and 40cm on strike 21. UFO Bowls have been pretty active this season. I've seen natural avalanches in #1 (point releases below cliff bands) and #2 (bottom half of the bowl). Today I talked to someone that saw the fracture from an avalanche in #3. I love getting up there but, for me, it'll be some time before stepping out onto those runs. Photo 1: Red line highlights weak layer at bottom of dust event. Below blue line is NFL. Photo 2: Hand hardness test.
Today's Observed Danger Rating
Considerable
Tomorrows Estimated Danger Rating
Considerable
Coordinates