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Observation: Moab

Observation Date
3/5/2018
Observer Name
T.Matthews
Region
Moab
Location Name or Route
SE Ridge of Mt. Tomasaki
Weather
Sky
Clear
Weather Comments
Hard to believe there wasn't any wind today during my travels. The slightest of breeze's from the N off and on, but not enough to transport snow. A far cry from yesterdays nuking winds. Temps felt warmer than they were without any wind.
Snow Characteristics
New Snow Depth
6"
New Snow Density
Low
Snow Surface Conditions
Powder
Damp
Snow Characteristics Comments
6" of new low density snow. I traveled up a S facing slope today at 11:00am the surface was still dry. By 11:30 it was starting to get damp. Without any wind to help keep the surface snow cool it got damp quicker than it likely would have. I'd expect to see another melt freeze crust on the surface of all SE, S, and W facing aspects tomorrow.
Red Flags
Red Flags
Poor Snowpack Structure
Red Flags Comments
Traveling up a Southerly aspect today I didn't expect to have any cracking or collapsing in the snowpack, and I did not. I suspect that with our poor structure had I been on a Northerly, or Easterly aspect I could have experienced some collapsing. At the location of my pit the new snow was not bonding well with the old snow surface. Which consisted of NSF's above a thin crust.
Avalanche Problem #1
Problem
Persistent Weak Layer
Trend
Same
Problem #1 Comments
I'd say with our poor snowpack structure and overall shallow depths it is likely you could find an persistent slab avalanche on steep NW,N, E facing slopes. On a 29 degree East facing slope at 10,700 feet I had an ECT and PST both fail and propagate across the entire column. I wouldn't want to temp fate on slopes steeper > 35 degrees.
Avalanche Problem #2
Problem
Wind Drifted Snow
Trend
Same
Problem #2 Comments
I did not travel in terrain today that had any recent wind loading. Although, judging from the nuking winds yesterday and the amount of scouring of terrain above treeline you could certainly find a wind slab avalanche on lee facing slopes, or in cross loaded gullies.
Snow Profile
Aspect
East
Elevation
10,700'
Slope Angle
29°
Comments
Location of pit produced ECTP's and propagation on a PST @30/100cm. New snow was not bonding well to the old snow surface which had some NSF's sitting on top of a melt crust.
Video
In this video I mention the ECT failing on the facets below the crust. After reviewing my notes this was not true. The CT, ECT, and PST all failed on the facets @31cm which is just above the crust. I ran the blunt end of the saw blade in the layer of facets below the crust. Which did collapse that weak layer. As I push the block off the PST notice that the facets above crust produce the sheer.
Mt. Tomasaki with all of it's wind damaged terrain. You might be able to find an avalanche in one of those cross loaded gully features.
Facet crust facet sandwich which was producing the snowpack test failures. The East face of Mt. Mellenthin.
Today's Observed Danger Rating
Moderate
Tomorrows Estimated Danger Rating
Moderate