Obs-Snow Profile: Red Pine Gulch 11/27/2011

Observer Name:

Patrick Fink

Region:

Red Pine Gulch
Little Cottonwood Canyon
Salt Lake

Observation Date:

11/27/2011

Location or Route:

South of Red Pine Lake

Weather

Sky:

Few

Wind Speed:

Calm

Weather Comments:

Beautiful weather all day-- and hot as all get out, even above 9000'.

Snow Characteristics

Snow Surface Conditions:

Faceted Loose

Wind Crust

Melt-Freeze Crust

Damp

Snow Characteristic Comments:

Below 9500', the snow surface was damp enough to glop up on my skins, though I saw few rollerballs.

Above 9500' in the open alpine the snow was largely wind impacted, buffed into pencil-hard slabs all over the place. Observed up to 10200 personally, though effect is obvious to ridge tops. The slabs are extremely stubborn and challenging to crack.

A west facing slope at around 10000' to the east side of red pine lake cut loose a wet slide just after I traversed across it. Point release from the rocks entrained snow about 4" deep and 7-8' wide that put about a foot of debris across the skin track. When I crossed this slope again 1.5 hours later, there was a second, similarly-sized debris pile right next to the first. Warm day today!

The warmer slopes had cooled by around 16:45 and were forming up into sun crusts.

Red Flags

Recent Avalanches

Rapid Warming

Red Flag Comments:

Though wind loading was widespread, the heat of the day today was the most attention-getting factor for me. I'm surprised that I didn't see more activity on sunny slopes.

Primary Concern

Primary Concern:

Persistent Slabs

Probability:

Low

Aspect:

North

Northeast

Northwest

Elevation:

High

Trend:

Same

Primary Concern Comments:

Tests continue to pull out on facets atop the october crust, which is now in some places pretty deep. These tests have grown more stubborn however, so I think that the probability of triggering one of these slabs is greater in areas with a thinner pack, as thicker wind-loaded slabs make it hard to trigger.

That said, extended columns and prop-saw tests show that once you hit it, it's ready to propagate. The consequences of affecting a collapse in these facets remains high.

The hardness of the facets seems not to be changing, ie. it's not healing. It's just being bridged over.

Secondary Concern

Secondary Concern:

Wind Slabs

Probability:

Low

Aspect:

North

Northeast

East

West

Northwest

Elevation:

High

Mid

Trend:

Same

Secondary Concern Comments:

As I mentioned above, the wind slabs are widespread, but very stubborn and hard (pencil).

That said, in places they're thick, and may actually be naturalling in the high terrain: see below.

Elevation:

10200'

Aspect:

North

Slope Angle:

snow_profile_location:

United States

40° 32' 16.8396" N, 111° 41' 28.77" W

Comments - Photos - Videos (group 1)

Despite the widespread wind-effect, there was still evidence of surface hoar growth on low angle (12-15) slopes around 9000', with a NW aspect.

Comments - Photos - Videos (group 2)

Spotted possible crowns on the peak to the southwest. Looks like wind slabs cracking out on NE facing slopes. There is a boot pack straight up the middle, between the two crowns.

Comments - Photos - Videos (group 3)

Given the warm temps, it's probably a good thing to remind everyone that there's no swimming in the lake.

Comments - Photos - Videos (group 4)

Video 4:

Observed Danger Rating:

Moderate

Forecast Danger Rating:

Moderate

Snow Profile Location

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