Observation: West Porter 3/7/2010

Observer Name:

Hardesty and Wagner

Observation Date:

03/07/2010

Region:

Salt Lake
Mill Creek Canyon
Porter Fork
West Porter

Weather

Sky:

Broken

Precipitation:

Light Snowfall

Weather Comments:

Perhaps half a trace of snow in the morning. Protected from the wind in this terrain. Warm temps, likely in the upper 20s.

Snow Characteristics

Snow Surface Conditions:

Powder

Melt-Freeze Crust

Damp

Snow Characteristic Comments:

Well crusted on the east, south and westerly aspects. Thick surface snow from Friday night's storm.

Red Flags

Recent Avalanches

Red Flag Comments:

Went to find the remote in West Porter triggered the day before. Slope angles as low as 28 degrees on a north facing slope at roughly 9000'. A steeper rollover off a micro-subridge rollover. Perhaps 50cm deep and 130' wide. Generally 1F hard soft slab, failing on the Feb 17 layer of Surface Hoar. The Feb 10th SH was found three inches beneath the bed surface. Surprisingly, ALL of our tests teased out the Feb 10th layer, but never provoked the failure plane from this slide.

Primary Concern

Primary Concern:

Persistent Slabs

Probability:

Moderate

Aspect:

North

Northeast

Northwest

Elevation:

Mid

Trend:

Less Dangerous

Primary Concern Comments:

Test after test after test. None showed red flag results - even in the fracture line. Again, looking at Strength, Structure and Energy.
ECTs - inconsistent initiation of failure plane(s). Never any propagation.
CTs - Never any Quality 1 shears at the SH layers. Only the Feb 10th layer produced any failure, though it was resistant to pop out.

Strength: All were in the Hard category. High strength.

Energy: All were Q2 at best. Planar, yet lacking pop, or energy. Moderate energy at best.

Structure: 5 Lemons - RED FLAG. Will remain so for quite some time. Still - think the layer is slowly gaining some strength.

snow_profile_location:

Comments - Photos - Videos (group 1)

Quite a widespread natural cycle of storm snow avalanches from early Saturday morning. Most 8" - 12" deep or so. Saw none that stepped down to SH layers.

We backed off a steeper feature in this terrain. Here's why: the SH layer was present in this area. A slide had occurred the day before. Ski cutting was not an option in this terrain and a ride would have been nasty. At best. Terrain in particular area was complex, steep prime terrain for SH up to 2' deep. Slap the skins back on and find something else.

Video 1:

Observed Danger Rating:

Moderate

Forecast Danger Rating:

Moderate