Pro Field Report

Basic Information

Observation Details

Observation Date:
December 8, 2019 - December 8, 2019
Submitted:
December 8, 2019
Observer:
SAC - Chago
Zone or Region:
Mores Creek
Location:
Almost Top of the World, Pilot Peak, 7500 ft, NNE

Signs of Unstable Snow

Recent Avalanches? 
None Observed
Cracking? 
None Experienced
Collapsing? 
None Experienced
Reactive/touchy test results.

Snow Stability

Stability Rating: 
Poor
Confidence in Rating: 
Low
Stability Trend: 
Steady

Bottom Line

Complexity and uncertainty situation for MCS. In just two visits we have identified reactive basal facets and today, buried surface hoar.

Media/Attachments

2.5-3mm SH buried 26-28 cm.
Surface Hoar crystals 2.5-3mm buried 26-28 cm under the snow surface.
Snowpit at Almost Top of the World, 7500 feet, NNE Aspect, 20 deg slope.
South Aspect at 7000 feet. Getting better!
CalTopo and GPS track for today

Advanced Information

Weather Summary

Cloud Cover:
Obscured
Temperature:
0 - +3 Deg-C
Wind:
Light , SW

LIght precipitation during the day. Foggy and warm, near freezing point. No evidence of snow transport during the storm.

Avalanche Observations

Foggy. Poor visibility inhibited detecting potential avalanches.

Snowpack Observations

Surface hoar buried 27-30 cms from the snow surface. Test results for layer of concern: CT1Q1(SC), ECTP2, CPST12/100(End), PST 15/120(Arr). Not reactive to ski cut, maybe due to un-cohesive slab and not yet sufficiently loaded. No Basal facets were detected today, unlike the basal facet layer observed 5 days ago at 8000 feet less than 1km from today's visited location. Between 40 to 60 cm depth there is a pencil hard crust layer.

Snowpit at Almost Top of the World, 7500 feet, NNE Aspect, 20 deg slope.
Surface Hoar crystals 2.5-3mm buried 26-28 cm under the snow surface.

Avalanche Problems

Problem Location Distribution Sensitivity Size Comments
Persistent Slab
Unknown
Unreactive
Stubborn
Reactive
Touchy
D1
D1.5
D2
D2.5
D3
D3.5
D4
D4.5
D5
 Layer Depth/Date: 26-28 cm
Comments: Surprised by the presence of buried surface hoar. It was not identified 5 days ago at Pilot Peak above 8000 feet. Will return tomorrow to characterize distribution.
Persistent Slab
Isolated
Specific
Widespread
Unreactive
Stubborn
Reactive
Touchy
D1
D1.5
D2
D2.5
D3
D3.5
D4
D4.5
D5
 Layer Depth/Date: 40 cm
Comments: Basal facets from October/November snow only observed at 8000 feet NW, N, NE aspects
Storm Slab
Isolated
Specific
Widespread
Unreactive
Stubborn
Reactive
Touchy
D1
D1.5
D2
D2.5
D3
D3.5
D4
D4.5
D5
 Layer Depth/Date: 20 cms

Is it possible to have areas at MCS with both avalanche problems; the basal facet (40-50 cm depth) and surface hoar (26-28 cm depth)? That is likely. We will know by tomorrow.

Terrain Use

Mores Creek Summit coverage is still poor. But the December 7-8 storm improved somewhat the access to skiable terrain above 7000 feet. Select terrain wisely, there are still plenty of p-tex eating sharks under the new snow.