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Observation: UFO Bowls

Observation Date
1/12/2019
Observer Name
Meisenheimer / Woodruff / Calaf
Region
Provo » American Fork » UFO Bowls
Location Name or Route
Aspen Grove to UFO Bowls
Red Flags
Red Flags
Poor Snowpack Structure
Red Flags Comments
We found places where the snow pack varied from 235 cm to 95 cm. My biggest concern would be areas that have a shallow snowpack (less than a meter of snow) with recent wind loading. We dug in an area with 95 cm of snow and found a mostly stable snowpack, albeit weak and faceted (lacking a slab).
Avalanche Problem #1
Problem
Wind Drifted Snow
Trend
Decreasing Danger
Problem #1 Comments
While walking around with UDOT forecaster John Woodruff AKA Woody, we discussed that we wouldn't feel comfortable walking in steep open bowls that have been effected by the wind. Our biggest concern would be where the wind deposited a slab on top of the weak December faceted snow. Most slopes went through a natural cycle during the Sunday/Monday (January 6th & 7th) wind and snow event. Although, it's hard to tell exactly which slopes remain intact and which ones avalanched during the storm at this point.
I would be very cautious approaching large and sustained terrain in the Temp Massif area for the time being. Too many lingering wind slabs along with a poor snowpack structure made us dial it back today.
Avalanche Problem #2
Problem
Persistent Weak Layer
Trend
Decreasing Danger
Problem #2 Comments
It's hard to ignore the fact that we have faceted snow in the snowpack. I am not exactly sure what it means at this point. However, I do know the structure of the snowpack is poor and there remains the chance of finding an area where you could trigger a lingering slab avalanche. Our group decided to approach steep terrain with caution. We avoided the steep N and NE aspects and still found soft settled powder.
Comments
Photo of our decent - we decided to avoid the steep NE face on our right. We determined there was no additional wind loading and felt good about being in this terrain, the snow was pretty shallow and was mostly all faceted. Again, my concern would be stumbling upon a wind loaded slope in the large open terrain. Mostly LOW danger with a pockety MODERATE danger for triggering a wind slab that fails into faceted snow.
Our snow pit shows a mostly poor snowpack structure. However, we felt comfortable as the whole snowpack was shallow and loose (no slab). It's also very likely that this pit was dug in a location that had avalanched previously. The snow to our left was 165 cm while this location was 95 cm. The good news is that, under the lens, most of the faceted grains were rounding and adjusting to the recent load. However, if we get additional water and wind out of the storm this next week - all bets are off. I wouldn't trust anything steep. Our score from the ECT test was negative. No propagation.
What a beautiful place to ski tour...
We did note a few large naturals that likely occurred during the past weekend storm. The grunge couloir flushed and triggered a larger chunk of snow in the apron. Likely 300' wide and 1-2 feet deep. Unable to get a good photo.
Today's Observed Danger Rating
Moderate
Tomorrows Estimated Danger Rating
Moderate