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Week in Review: Jan 1 - 7, 2021

Greg Gagne
Forecaster
Our Week in Review highlights significant snowfall, weather, and avalanche events of the previous week. (Review the archived forecasts for the Salt Lake mountains.) 
The danger roses for the Salt Lake mountains from Friday, January 1 through Thursday, January 7:
Summary: Two small storms (totaling roughly 12" snow and 1" of water), some wind, and lots of human-triggered avalanches (More than 20 human-triggered avalanches reported to the UAC) including remotely-triggered and avalanches that were sympathetically released (one avalanche causing another.) Almost all activity involved avalanches failing in weak, faceted snow now buried 1-2.5' deeply. A heat map showing the distribution of avalanches in the Salt Lake mountains over this past week.
Thanks to everyone for reporting all of these avalanche involvements, and fortunately we are not aware of any injuries.
Friday, January 1: Cold and clear skies greet the New Year. Two human-triggered avalanches are reported from the backcountry:
No Name Bowl along Park City ridgeline. East aspect at 9400'. 12" deep, 150' wide, 500' vertical. Failed on facets and took out old tracks. [M. white photo]
Chicken S#!T Ridge (Days Fork) on a northeast aspect at 9500' Although relatively small (10' wide while running 50' vertical), this slide also failed on weak faceted snow.
Saturday, January 2: A human-triggered avalanche in Rocky Point near Catherine's Pass. This slide was on a wind-loaded slope on a northeast aspect at 10,200' It was 2.5' deep, failing in weak, faceted snow.

Sunday, January 3: 1-4" of new snow and moderate to strong winds out of the southwest, especially at the upper elevations. No avalanches reported from the backcountry.
Monday, January 4: Another human-triggered avalanche on Sound of Music along the Park City ridgeline - Sound of Music. An east aspect at 9,200'. The rider was well down the slope when the avalanche released from above.
Tuesday, January 5: 8-10" of new snow (containing 0.75 - 0.9"of water) with moderate to strong westerly winds with clearing skies during the afternoon. TEN human-triggered avalanches were reported to the UAC. These all failed in weak, faceted snow and were up to 2.5' deep and up to 150' wide. One of the more notable avalanches occurred in West Monitor Bowl along the Park City ridgeline. The first avalanche was remotely triggered and this avalanche sympathetically released a second avalanche:
Wednesday, January 6: A lone skier triggers an avalanche in West Monitor Bowl - adjacent to the two avalanches described above. Also, another Park City ridgeline human-triggered avalanche on SquareTop (notice the addtional slide in the shade to the looker's right)
Thursday, January 8: Another remotely-triggered slide, this one in upper Big Cottonwood canyon in Martha's Bowl below Pioneer Peak: