Observation: Monitors

Observation Date
1/7/2021
Observer Name
Greg Gagne
Region
Salt Lake » Park City Ridgeline » Monitors
Location Name or Route
Park City Ridgeline / Monitors
Weather
Sky
Broken
Wind Direction
West
Wind Speed
Moderate
Weather Comments
Sustained gusty winds along ridgetops.
Snow Characteristics
Snow Surface Conditions
Dense Loose
Faceted Loose
Wind Crust
Melt-Freeze Crust
Damp
Snow Characteristics Comments
Snow surface is faceting with radiation recrystallization found on some solar aspects - a thin 5mm layer of facets atop a crust. (Only becomes an issue if buried underneath new snow or wind-blown snow.)
Also beginning to notice "sandboxing" in thinner snowpack areas as any stronger snow atop of the facets continues to weaken and skis are starting to crash through to the ground.
Red Flags
Red Flags
Recent Avalanches
Wind Loading
Cracking
Collapsing
Poor Snowpack Structure
Red Flags Comments
5 Red Flags, with recent avalanches dominating. Several loud booming collapses.
Avalanche Problem #1
Problem
Persistent Weak Layer
Trend
Same
Comments
Cruised Park City ridgeline today - this zone has been *very* active this week with numerous human-triggered slides. Focused on the Monitors as it now has three human-triggered slides in the past few days. The snowpack along the Park City ridgeline is typically weak even in a "good" year. But take a "bad" year, add an inch of water, wind, and some folks on skis/snowboards and you have an avalanche factory.
Most avalanches in this zone were triggered on slopes with denser slabs of wind-blown snow. In areas where there wasn't a stronger slab on top, pit results were ECTN. But where there was a stronger slab (mostly due to recent wind-loading, full propagation in extended column tests, with scores in the 20's.
Video
Today's Observed Danger Rating
Considerable
Tomorrows Estimated Danger Rating
Considerable