Observation: Flagstaff Ridge

Observation Date
12/17/2021
Observer Name
Nate L
Region
Salt Lake » Little Cottonwood Canyon » Flagstaff Ridge
Location Name or Route
Flagstaff
Red Flags
Red Flags
Recent Avalanches
Heavy Snowfall
Wind Loading
Avalanche Problem #1
Problem
Wind Drifted Snow
Trend
Decreasing Danger
Problem #1 Comments
Observed heavy winds from the W through SW with abundant snow available for transport. Sastrugi were common on the Flagstaff shoulder and snow was clearly being deposited on the east side of the shoulder. I noticed at least one rounded pillow of snow which could have been a wind slab, in steep enough terrain to slide. Good reminder that wind and new snow related instabilities still provide danger on southerly aspects as long as we have wind & new snow for transport.
Comments
With all the talk of facets on northerly aspects, I decided to dig a snowpit on a southerly aspect for a new perspective. Dug in the meadow at the base of the flagstaff shoulder, slope angle <10 degrees, directly south-facing. HS 95cm, generally right-side-up, progressing from fist-hard at the surface powder to finger-hard in the 12/9 storm snow. 35cm and below was ice, at least pencil-hard. There was a slight density inversion from 35cm to 40cm of 4F hard snow, underneath a layer of 1F-hard snow, but this layer was not reactive in snowpit tests (ECTX) and will probably settle out. This provides a good reminder that there's plenty of safe powder to be enjoyed on southerly aspects, as long as one is careful not to allow subtle terrain variations to put them on a northerly aspect. Estimated danger ratings below are for SE-S-SW aspects only.
Today's Observed Danger Rating
Moderate
Tomorrows Estimated Danger Rating
Low
Coordinates