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Observation: Maple Hollow

Observation Date
2/21/2018
Region
Southwest » Pahvant Range » Maple Hollow
Location Name or Route
Pahvants - Maple Hollow
Weather
Sky
Scattered
Wind Speed
Calm
Weather Comments
Started out cold (10 degrees) and partly cloudy then cleared.
Snow Characteristics
New Snow Depth
16"
New Snow Density
Low
Snow Surface Conditions
Powder
Snow Characteristics Comments

HST=16" from last storm on Monday.

Trail breaking was hard, as Seth Shaw would say "a two sandwich day"

Red Flags
Red Flags
Cracking
Collapsing
Poor Snowpack Structure
Red Flags Comments
2 large collapses, I was surprised there were not more. Lots of cracking during last storm, see photos below. None today. Poor snowpack structure, nothing new here.
Avalanche Problem #1
Problem
New Snow
Trend
Same
Problem #1 Comments

Today I was most concerned with the new snow. However, persistent slabs was not far behind.

There is enough new snow sitting on some weak surfaces to warrent cuation.

Considerable danger.

Avalanche Problem #2
Problem
Persistent Weak Layer
Trend
Same
Problem #2 Comments

Facets in the lower pack as well as a weak mid-pack are a significant concern with the new weight.

Considerable hazard.

Snow Profile
Aspect
Northeast
Elevation
9,000'
Slope Angle
25°
Comments

HS=44", not bad for a weak winter.

2 mm basal facets, rounding but loose (fist)

The mid pack consist of alternating crust (wind/warm?) and rounding facets 1 mm and less. The upper pack is sitting on a suncrust (uppermost horizontal line), facets at the base of this crust (ECTP 15, Q1.5, it had a nice pop on release).

One micro crust in upper pack which consists of recent storms.

Photo below ECTP, pole points to failure plane.

Photos below, activity from last storm on Monday.

1. 8,000, on approach, this reminds me while I backed out of coming here Monday, the summer trail crosses some steep terrian that I typically do not worry about. Slope is 37-40 degrees. sunny aspect

2. Gully below summer trail, shady aspect 8,000' elevations.

3. Main meadow I skied near pit location, this collapse did not run due to slope angle 25-30 degrees. The whole meadow was completely cracked with transverse cracks. and some additional collapse areas.

4. Cracks just below ridge, 9,200'.

Overall, all activity I saw (a lot) was all in the new snow and look like it happened during the storm which had some high PI rates.

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.

Overall I would say a considerable hazard, I traveled very cautiously and avoided my typical exit for this area which contains some steep slopes.

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