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Observation: Maple Hollow

Observation Date
2/25/2018
Observer Name
Toddeo
Region
Southwest » Pahvant Range » Maple Hollow
Location Name or Route
Pahvants - Maple Hollow
Weather
Sky
Clear
Wind Direction
West
Wind Speed
Light
Weather Comments
Started out cold, got warm enough to lightly affect snow on some east aspects.
Snow Characteristics
New Snow Depth
6"
New Snow Density
Low
Snow Surface Conditions
Powder
Damp
Snow Characteristics Comments

1" in town, 4" at 6,500' trailhead. HST 4-6". I only made it to 8,200' today. There is 16" sitting on the most recent suncrust on protected east aspects at 7,800'. Recent storms are enough that driving to the 6,500' trailhead may not be possible after the next storm. I was the only pilgrim to drive in this morning.

Red Flags
Red Flags
Poor Snowpack Structure
Red Flags Comments
On north aspects the facets are not healing very well. I also skied a couple of runs on a NW aspect, still punchy. Lot's of signs of wind loading including drifts up to 3' deep, all nonreactive.
Avalanche Problem #1
Problem
Persistent Weak Layer
Trend
Same
Problem #1 Comments

Somewhere between persistent and deep slab, an ECTP broke at 3.5' below the surface (see below) Mostly on the north 1/3 of the compass.

Still fist hardness facets down deep.

Avalanche Problem #2
Problem
Wind Drifted Snow
Trend
Same
Problem #2 Comments

Wind slabs in many areas, although generally nonreactive, they have added additional load to the facets.

Snow Profile
Aspect
Northeast
Elevation
8,100'
Slope Angle
25°
Comments

HS-48"

Of note: Two areas of basal facets separated by a decomposing melt-freeze crust. The lower part of the mid-pack has consolidated to 2-finger hardness. Still very easy to isolate columns to the ground with a ski pole.

ECTP 21, Q2.5 at 40" below the surface (Yikes!) in the facets above the melt-freeze crust. This is spooky for several reasons including:

It is greater than 3' down, which is where it is supposed to be hard for a skier to trigger something from the surface. I typically feel 3' is not enough of a cushion.

It is late February, basal facets are typically healed way before now. I am not confident that they will heal at all this year.

Photos below:

1. ECTP 21 Q2.5 results, glove sitting on failure plane, facets on top of crust.

2. facets, rounding a bit but still very loose and weak.

Other photos:

1. Wind affect

2. Trenching thru wind drifts.

Overall a solid Considerable hazard above 8,000' on north aspects. I felt like I was tip-toeing around all day.

If anyone wants to get in touch with me about snow/avalanche questions in SW Utah, I can be reached at [email protected]. I would be happy to walk anyone through the observation process. All observations are appreciated.

Today's Observed Danger Rating
Considerable
Tomorrows Estimated Danger Rating
Considerable