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Observation: Alta Periphery

Observation Date
4/5/2022
Observer Name
Hardesty
Region
Salt Lake » Little Cottonwood Canyon » Alta Periphery
Location Name or Route
Alta perimeter
Weather
Sky
Overcast
Precipitation
Light Snowfall
Wind Direction
Northwest
Wind Speed
Strong
Weather Comments
Merciless northwest winds....
Snow Characteristics
New Snow Depth
4"
New Snow Density
High
Snow Surface Conditions
Powder
Snow Characteristics Comments
Fast and surfy graupel skiing. Excellent, especially on lower angle terrain to keep from bottoming out on the old crusts.
Red Flags
Red Flags
Wind Loading
Avalanche Problem #1
Problem
Wind Drifted Snow
Trend
Decreasing Danger
Problem #1 Comments
Many northerly starting zones scoured. Despite the unyielding winds, I found no evidence of reactive wind slabs on any aspect. I expected to find drifts well down below standard loading zones and channeled onto a variety of aspects but nothing moved or cracked out. Most of the new snow was high density and graupel.....
Avalanche Problem #2
Problem
New Snow
Trend
Decreasing Danger
Problem #2 Comments
The pre-frontal inch of snow came in warm and bonded well to the warm corrugated crusts on east>south>west aspects. 2-3" of large diameter graupel fell during and just after frontal passage with an inch of high density snow to follow. Photo.
On northerly aspects, tests elicited shear planes above and below a thin crust (see profile), but no problematic facets or weak layer concerns me here.
Pic 1, 2 - shallow wind "slab" over graupel with good bond to crust
Pic 3 - photo of profiled northerly aspect in catherine's
Snow Profile
Aspect
North
Elevation
10,000'
Comments
For Wednesday: Isolated concerns include graupel pooling in aprons below steep chutes (Wolverine perhaps) with isolated pockets of wind drifts found in these mid-slope areas as well. These pockets may still be at play on Wednesday. Wet loose sluffs may be expected with sun and heating.
Today's Observed Danger Rating
None
Tomorrows Estimated Danger Rating
None
Coordinates