Observation: Butler Basin

Observation Date

1/14/2025

Observer Name

Hardesty and Pagnucco

Region

Salt Lake » Big Cottonwood Canyon » Butler Fork » Butler Basin

Location Name or Route

Butler Basin

Weather

Sky

Few

Weather Comments

Glorious. No wind. Cold.

Snow Characteristics

New Snow Depth

10"

New Snow Density

Low

Snow Surface Conditions

Powder

Damp

Snow Characteristics Comments

Excellent right-side-up storm snow. Warm enough for many solars to have a zipper crust Wednesday morning. This crust may become an RR crust; the subsurface snow a cm below the surface cold snow was still damp and had not yet frozen. With the phase change, facets may form this afternoon/eve. Take a look.

Avalanche Problem #1

Problem

Persistent Weak Layer

Trend

Same

Problem #1 Comments

Travel was up into upper Butler Basin to look at the avalanche involvement from Sunday. On route we did not see any new avalanches or experience any cracking or collapsing.

Snow profile is below. Average HS in these mid-elevations was 140-170cm with 4F/4F+ basal facets. It would be unlikely that this would be a trigger point on the slope; instead one would need a much thinner or rockier zone as we saw with this accident or a repeater slope that did not take out the facets the first time.

It's really a tale of two snowpacks: Solars (first photo) that hold no uniform and/or unstable snow and polars that do. Worse yet, the polar stability (second/third photos) is increasing but is not yet stable. What this means of course is that parties will not see signs of instability and may ride a few slopes before they find a trigger spot. This is a dangerous setup...and low angle with nothing steep above is the only path for riding on polar aspects. Sorry for the soap box.

Avalanche Problem #2

Problem

Wet Snow

Trend

Increasing Danger

Problem #2 Comments

Tomorrow's 700mb temps rise toward +1C with mostly clear skies and light wind. Even though the steep solar aspects have been kissed by the sun the last two days, this will be a dramatic warm up: Wet loose and pockety "wet slabs" likely in steep sun-drenched terrain.

*There is a LOT of cold low density snow that will see a lot of heat tomorrow. I would imagine impressive debris piles under steep sustained slide paths on the sunny aspects.

Snow Profile

Aspect

Northwest

Elevation

9,300'