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Observation: Moab

Observation Date
12/12/2022
Observer Name
Garcia
Region
Moab
Location Name or Route
Laurel Highway
Weather
Sky
Obscured
Precipitation
Moderate Snowfall
Wind Direction
Southwest
Wind Speed
Moderate
Weather Comments
S2 snowfall for most of the day with short breaks every now and then.
Snow Characteristics
New Snow Depth
9"
New Snow Density
Low
Snow Surface Conditions
Powder
Red Flags
Red Flags
Heavy Snowfall
Wind Loading
Cracking
Poor Snowpack Structure
Red Flags Comments
Snowfall rates were about an inch/hour all day. Blowing and drifting snow was obvious. Moderate to strong winds out of the SW drifted N and E facing slopes. I experienced a good amount of cracking today. Not enough to be considered widespread. Cracking was limited to the new snow only. Failure was occurring on the new/old snow interface. New snow was poorly bonded to the old surface snow. Poor snowpack structure was observed in a NE facing pit at 11,090 ft. A weak layer of facets is 55cm below the surface.
Avalanche Problem #1
Problem
Persistent Weak Layer
Trend
Same
Problem #1 Comments
9 inches of new snow and 0.7 SWE (at 3:30PM). It looks like its going to take more to bring the house down, but once again we are teetering on the edge with another smallish loading event. I did not experience collapsing today. I got 2 ECTX results in my pit on a NE face at 11,090. Don't let this result fool you. I continued tapping from the shoulder after the standard 30 taps and got full propagation with sudden planar shears on two occasions at 34, and 32 taps. This doesn't inspire a ton of confidence in our snowpack. This tells me there is a slab above a weak layer and it is capable of producing avalanches. The weak layer of facets sits 55cm below the surface. These facets are 1.5 mm in size and fall out of the pit wall with ease. It's an obvious strong snow over weak snow set up and is not to be trusted.
I also dug on a SW face at 11,140 ft. I found right side up snow on top of a 15cm thick knife hard crust that is really hard to get a shovel through. There are facets on the ground below this crust. Due to the extremely hard nature of this crust, I do not expect to see avalanches breaking down to these facets on the ground.
Avalanche Problem #2
Problem
Wind Drifted Snow
Trend
Same
Problem #2 Comments
9 inches of new snow available for transport. Winds today were moderate to strong out of the SW. I noticed plenty of blowing and drifting occurring.
Snow Profile
Aspect
Northeast
Elevation
11,100'
Slope Angle
32°
Photo 1: Cracking in storm snow
Photo 2: NE pit after the slab pulled out
Photo 3: SW pit. The 15cm thick knife hard crust is directly above the facets on the ground.
Today's Observed Danger Rating
Considerable
Tomorrows Estimated Danger Rating
Considerable
Coordinates