Obs-Snow Profile: Alta Periphery 12/22/2011

Observer Name:

Greg Gagne

Observation Date:

12/22/2011

Region:

Salt Lake
Little Cottonwood Canyon
Alta Periphery

Location or Route:

Alta Periphery

Weather

Sky:

Few

Wind Direction:

Northeast

Wind Speed:

Moderate

Weather Comments:

Temp -15C. Winds seemed to moderate as the morning progressed.

Snow Characteristics

New Snow Depth:

New Snow Density:

Low

Snow Surface Conditions:

Powder

Wind Crust

Snow Characteristic Comments:

Widespread wind affected snow on a variety of aspects with some cross-loading. Was finding about 10-15 cm (4-6") light density snow outside of wind affected areas. Some areas were scoured from the NW->NE winds. In areas that were wind loaded, was finding 4F slabs 15-30 cm (6-12").

Red Flags

Wind Loading

Cracking

Primary Concern

Primary Concern:

Wind Slabs

Probability:

Moderate

Aspect:

North

Northeast

West

Northwest

Elevation:

High

Mid

Trend:

Same

Primary Concern Comments:

Am including aspects facing West as I observed wind drifting along higher ridgelines from the NE/E winds.

snow_profile_location:

Comments - Photos - Videos (group 1)

Was finding fairly wind-spread wind affected snow with wind drifts even off of the ridge lines. Where there was wind-drifted snow, I was having a hard time isolating a column on steeper aspects as it was failing in the faceted snow just underneath the new snow. Ski cuts on steeper aspects would gouge the new snow well down into the very weak old snow. Agree with Bruce's assessment this morning that problem areas are likely confined to areas that were wind-loaded. Overall I was finding the fresh wind slabs to crack out somewhat, but they were less sensitive than I was expecting. Am curious what others were finding.

Snow profile is a composite of what I was observing today.

Observed Danger Rating:

Moderate

Forecast Danger Rating:

Moderate