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Observation: Main Porter

Observation Date
12/17/2023
Observer Name
Gagne/Davies
Region
Salt Lake » Mill Creek Canyon » Porter Fork » Main Porter
Location Name or Route
Main Porter Fork
Weather
Sky
Few
Weather Comments
Clear and calm.
Snow Characteristics
Snow Surface Conditions
Faceted Loose
Damp
Snow Characteristics Comments
Widespread near-surface facets on everything with a shady aspect, including some 4-8 mm surface hoar in drainage bottoms. Solar aspects were taking on yet another day of strong warmth and this long string of warm, sunny days is thinning out the snowpack on southerly aspects.
HS (height of snow) in Porter Fork is 30-60 cms below 8,500', with the deepest we were finding was 90 cms above 9,000'
Ski penetration is 5-10 cms which tells us the snowpack is still supportable.
Red Flags
Red Flags
Poor Snowpack Structure
Comments
The video below describes what we were seeing today. Two highlights:
We got ECT propagation with two pits, failing in faceted snow and depth hoar 5-10 cms above the ground. The scores were ECTP22 and ECTP26. This highlights how deceptive persistent weak layers can be and that an avalanche could still be triggered from the right spot.
The entire snowpack is weakening, with the top 10-15 cms becoming all near-surface facets and even the stronger slab below starting to facet. When we do place a load of new snow on top, there are plenty of weak layers for avalanching.
Video
On my tours and field work this weekend, I was out with regular touring partners and we practiced beacon drills, probing, and strategic shoveling. High pressure periods are an ideal time to practice these skills.
Today's Observed Danger Rating
Low
Tomorrows Estimated Danger Rating
Low
Coordinates