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Observation: James Peak

Observation Date
12/19/2020
Observer Name
Gagne/Duvernay
Region
Ogden » Powder Mountain Backcountry » James Peak
Location Name or Route
Lightning Ridge & James Peak
Weather
Sky
Overcast
Wind Direction
West
Wind Speed
Light
Weather Comments
Mid-level clouds obscured views much of the day. Light westerly winds.
Snow Characteristics
New Snow Depth
6"
Snow Surface Conditions
Powder
Dense Loose
Snow Characteristics Comments
The Thursday/Friday snowfall was rather dense: 10-12%. This made for good travel and riding conditions in this lean snowpack. HS ranges from 30-75 cms.
Red Flags
Red Flags
Cracking
Collapsing
Poor Snowpack Structure
Red Flags Comments
We had numerous loud collapses and cracking.
Avalanche Problem #1
Problem
Persistent Weak Layer
Trend
Same
Problem #1 Comments
Lots of collapsing and cracking today on all aspects other than southeast, south, and southwest. Most prominent was a weak 5 cm layer of near-surface facets underneath 15 cms of Thursday/Friday storm snow. However, it seems there isn't quite enough of a cohesive slab on top of these facets. This layer of facets is on top of a temperature crust on aspects facing west, northwest, northeast, and east. STE shovel shear test. Most pits were ECTN, but we did get ECTP3 down 15 cms on the facets above this crust on a north-facing slope at 9,000'.
This is an issue in areas with a deeper slab on top - those that received more storm snow (greater than 20 cms/8") or in areas where there is wind-drifted snow.
Snow Profile
Aspect
North
Elevation
9,000'
Comments
Our travel today involved looking at all aspects between the narrow elevation band of 8300' and 9000'. Faceted snow existed on all aspects other than southwest and south. We had lots of collapsing and cracking, but despite the poor snowpack structure, there doesn't seem to be enough of a slab on top of the weak facets for it to be a widespread problem at the moment. I am more concerned with this weak structure in areas that received more snow or wind-blown snow.
Video
Where we were traveling it was a Moderate danger. However, on aspects with a PWL and a deeper slab on top of the facets, there remains a Considerable danger of triggering an avalanche that fails in faceted snow.
Huge thanks to Powder Mountain snow safety team for helping arrange travel today!
Today's Observed Danger Rating
Considerable
Tomorrows Estimated Danger Rating
Considerable