Pro Field Report

Basic Information

Observation Details

Observation Date:
March 15, 2021
Submitted:
March 16, 2021
Observer:
SAC - VandenBos, VandenBos, Gall
Zone or Region:
Galena Summit and Eastern Mtns
Location:
Butterfield (6,700-9,700', N-NE-E-SE-S-SW)

Signs of Unstable Snow

Recent Avalanches? 
None Observed
Cracking? 
None Experienced
Collapsing? 
None Experienced

Advanced Information

Weather Summary

Cloud Cover:
Mostly Cloudy
Wind:
Light

Clear skies in the morning, with clouds beginning to build around noon. Skies were BKN, approaching OVC by mid-afternoon, then clearing a bit in the late afternoon. A few light squalls from convective showers produced no accumulation. Winds blew light from a variety of directions.

Avalanche Observations

No recent avalanches observed.

Snowpack Observations

Crusts on solar aspects broke down quickly at lower elevations, hung on a bit longer up above 8,000'. Surfaces were melted by mid-morning, but began to refreeze quickly as clouds covered the sun. By exit from the field (1600) these surficial crusts were 1-2cm thick. Mid-pack crusts on solars had accumulated a decent bit of melt-water from earlier freeze-thaw cycles, producing ice lenses up to 3-4mm thick. I dug at 8,600' on a SE aspect where HS=90cm. There was water present throughout the snowpack, particularly in the upper 30-40cm. Basal facets (12/11) were moist approaching wet. ECTs produced ECTXs and ECTNs in the upper 20s on mid-pack interfaces. At lower elevations, a weak freeze overnight, solar input, and ambient warm air had produced a snowpack that was trending towards being cohesionless, but I did not encounter this on slopes where it would be problematic.

Avalanche Problems

Problem Location Distribution Sensitivity Size Comments
Wet Loose
Isolated
Specific
Widespread
Unreactive
Stubborn
Reactive
Touchy
D1
D1.5
D2
D2.5
D3
D3.5
D4
D4.5
D5
 Comments: Rose shaded based on where I encountered snow that may have been problematic in steeper terrain. Suspect a lot of the steeper terrain in these areas has already run through multiple wet loose cycles, limiting the likelihood of this problem.

Terrain Use

Traveled in avalanche terrain up to 35 degrees.