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Observation: Dark Canyon

Observation Date
2/18/2025
Observer Name
Trenbeath
Region
Moab » Dark Canyon
Location Name or Route
Dark Canyon
Weather
Sky
Clear
Wind Direction
Northwest
Wind Speed
Light
Weather Comments
Beautiful winter day in the mountains with light to calm winds, and cold temperatures in the mid teens to low 20's depending on elevation. Strong sun made it feel warmer than it was.
Snow Characteristics
Snow Surface Conditions
Powder
Dense Loose
Damp
Snow Characteristics Comments
It's been four days since the storm when we picked up 15" of new snow at 2.4" SWE. NW winds over the past couple of days have affected the surface to varying degrees in open areas but abundant soft snow can still be found. Solar aspects were getting damp from the strong sun.
Great to finally see some snow but conditions remain thin, especially on solar aspects. Open areas had varying degrees of wind affect.
Red Flags
Red Flags
Wind Loading
Poor Snowpack Structure
Red Flags Comments
I observed areas with recent deposits of wind drifted snow, primarily above treeline on N-NE-E aspects. Wind slabs are generally located in areas where the main threat is triggering a deeper avalanche on buried facets. Northerly aspects are very weak with faceted layers from top to bottom beneath the most recent snow. Depths range from 100-140 cms. Southerly aspects are much thinner, and many were bare prior to the last storm. I observed facet crust combinations on these aspects but did not observe a widespread weak layer.
Avalanche Problem #1
Problem
Persistent Weak Layer
Problem #1 Comments
Although the entire snowpack on northerly aspects is faceted beneath the recent snow, the primary layer of concern has been the old snow surface. 2" of snow fell on Feb 11 and subsequently faceted. This weak layer produced widespread collapsing over the weekend, and stability tests produced easy failures. In my travels today I did not observer any collapsing of the snowpack, but an extended column test on a NE aspect at 11,000' produced results of ECTP17 on this faceted layer.
I also dug pits on SE and SW aspects at around 10,800' but I did not find the Feb 11, faceted weak layer. Extended column tests produced no results in either pit.
SW aspect at 10.800' New snow above a stout crust with a layer of facets underneath. ECTX, no results.
SE aspect, 10,600'. Recent snow on top of a thick, pencil to knife hard melt freeze layer. ECTX, no results.
Avalanche Problem #2
Problem
Wind Drifted Snow
Problem #2 Comments
I observed areas of wind drifted snow on upper elevation north through easterly aspects. These should be stabilizing with the greatest concern being the additional stress they are adding to persistent weak layers. I did not observe any wind slab instability near treeline or below.
Snow Profile
Aspect
Northeast
Elevation
11,000'
Slope Angle
22°
Comments
The current snowpack is tenuous and variable although it is showing a trend toward greater stability since the storm on February 14. In my travels today, I observed no collapsing of the snowpack whereas it was widespread a couple of days ago. The most consistently poor snowpack structure exists on northerly aspects near treeline and below where recent snow has stressed the underlying, faceted snowpack. The February 11, faceted layer also appears to be the most widespread in these areas. Above treeline northerly aspects display much more variability due to heavy wind erosion during the January high pressure. On southerly aspects, the distribution of the February 11, faceted layer is also quite variable due to periods of moderate to strong SW winds. Additionally, southerly aspects lacked consistent snow cover prior to February 11, and the storm on Feb 14, to make this a widespread problem in these areas.
Today's Observed Danger Rating
None
Tomorrows Estimated Danger Rating
None