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Observation: Thomas Fork

Observation Date
3/5/2023
Observer Name
Gagne/Johnston/Frey/Griffiths
Region
Salt Lake » Neffs » Thomas Fork
Location Name or Route
Thomas Fork Neffs Canyon
Weather
Sky
Broken
Precipitation
Light Snowfall
Wind Direction
West
Weather Comments
Evolving weather ranging from overcast to bits of sunshine to short, intense snow squalls.
Snow Characteristics
New Snow Depth
12"
New Snow Density
Medium
Snow Surface Conditions
Powder
Snow Characteristics Comments
5-10 cms at 5,700' TH and up to 30 cms at 9,700' Slight density inversion within storm snow.
Red Flags
Red Flags
Recent Avalanches
Heavy Snowfall
Cracking
Red Flags Comments
We saw widespread evidence of natural avalanches that occurred during the overnight hours, likely during periods of higher precipitation intensity - photos below. Some cracking within the storm snow on steeper slopes, failing within a density inversion down 15-20 cms.
Avalanche Problem #1
Problem
New Snow
Trend
Increasing Danger
Problem #1 Comments
Heavy snowfall over a short duration meant it was time to step back today. Although Neffs Canyon got half the amount of storm snow than the Cottonwoods, there was still a natural avalanche cycle as low as 7,500'. Storm snow instabilities will rapidly settle out, but with another storm approaching overnight, we'll likely be back to another New Snow avalanche problem for Monday.
Comments
We did not see any widespread wind-drifting, but there was a natural avalanche cycle and the new snow still needs time to settle for stabilization and we stepped back and stayed on lower-angled slopes and avoided runout zones. Shovel tilt tests produced shearing within density inversion.
Most of the natural avalanche activity seemed to be shallow, but we did see debris from larger slides that originated on the north face of Peak 9,773' at the head of Thomas Fork.
Photos of some natural avalanche activity (always a red flag) as well as some cracking.
Given this area didn't get the snow amounts nor apparent wind loading, it was solid Considerable.
Today's Observed Danger Rating
Considerable
Tomorrows Estimated Danger Rating
High
Coordinates