Observation Date
12/20/2021
Observer Name
Hardesty
Region
Salt Lake » Cottonwood Canyons
Location Name or Route
Cottonwood ridgeline
Comments
I did remotely trigger a cornice overhanging the Silver Fork headwall on the ridgewalk today, but the dining room table cornice did not trigger an avalanche below. Photo below.
I was able to view a bit of the range today with clear skies and a good monocular. I was surprised to see how much snow remained on the hillsides. In other words, it didn't appear we went through a significant natural avalanche cycle last week; rather it was enough to make the snowpack conditionally unstable....just waiting for a trigger. And we have a lot of triggers in the Wasatch. While the current poor structure remains dangerous, it is clearly not as hair-trigger as it was late last week into Saturday. Perhaps - as Greg wrote on Friday - this may lure people into thinking things are safer than they are. They are not.
My concerns then, heading into the holdays with a series of storms on tap are - well - that we may have the perfect storm for more close calls and accidents or worse. Some conjecture below -
- Repeater avalanches may be possible with the heavy snowfall and wind. Many of the avalanches either did not take out all of the PWL at the bed surface....and/or the decomposing thin/friable crust with facets above/below will not hold much of a load.
- On slopes that didn't avalanche, the slab hardness is trending One Finger>Pencil and I fear that with enough loading (heavy snowfall and wind), we may see much larger avalanches propagating over wide distances. By then the slab depth may average 3-5' deep.
- We'll be keeping an eye on the weakening surface snow in the coming day(s). It may be that the new snow bonds poorly on the shady slopes.
We'll see. Big picture - we expect the danger to ramp up again in the coming days.

Today's Observed Danger Rating
Considerable
Tomorrows Estimated Danger Rating
None
Coordinates