Date of Observation: 01/31/2022
Name: Eric Murrow
Zone: Southeast Mountains
Route Description: Ascended Red Lady skin track to Gunsight Pass to Scarp Ridge. Descended The Shield into Redwell Basin out to Oh-Be-Joyful Creek. We traveled down the line between the Southeast and Northwest Forecast Zones.
Observed avalanche activity: Yes
Avalanches: We skier-triggered a tiny, shallow slab above treeline beneath a mid-slope rollover and were able to trigger Loose Dry avalanches below treeline on steep, northeast-facing terrain.
Weather: Cold valley bottom temperatures gave way to milder air temps up high. Thin, high clouds moved overhead mid-morning and departed around 1pm. West-northwest winds blew at moderate speeds transporting some snow, but little effective loading.
Snowpack: On the ascent, I dug a few hasty pits into south-facing terrain on steep slopes, I generally found a stout melt/freeze crust at the surface 3-4 inches thick with ice columns and lenses up to a foot below the surface. Did not travel over southeast-facing terrain, but easterly slopes in the area were completely dry so the stout crusts on the south aspects slowly taper out of existence by the time you hit due east.
Northerly alpine terrain is a mix of wind-board and soft, faceted surfaces. Places touched by the wind, yet still soft, did not produce Loose Dry avalanches, but we did trigger a small slab beneath a rollover. As we descended to near and below treeline terrain on east and northeast aspects the faceting process at the surface became far more significant. Sheltered slopes facing east and northeast have up to 10 inches of cohesionless snow for Loose Dry avalanches with facet grain size commonly at 1mm with some grains nearing 2mm. We traveled on small slopes at lower elevations so triggered Loose avalanches remained D1 in size, but they were fast-moving and gained mass as they ran.
Photos:
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Facets from near the surface on a northeast slope below treeline. 1-1.5mm in size with a few nearing 2mm. Facets are becoming solid and chunky with very little to no cohesive properties.
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A quick look at the stout melt/freeze crusts on south aspects. Ice columns from melt water freezing were present a foot below the surface.
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Northeast alpine terrain with a mix of thin wind board and soft, faceted surfaces. The wind has formed isolated, shallow slabs across this slope.
Estimated avalanche date: 01/31/2022
Number of Avalanches: 1
Location
Location: Mount Emmons
Location Specific:
Start Zone Elevation: ATL: Above Tree Line
Aspect: NE
Characteristics
Trigger: Skier
Trigger modifier:
Type: Soft Slab
Failure Plane:
Size
Relative Size: R1 very small
Destructive Size: D1- Relatively harmless to people
Avg. crown height (inches):
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Involvements
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Additional comments: Tiny, soft slab on a mid-slope rollover. Completely harmless in size, but nearby features likely could have produced other small slabs.
Estimated avalanche date: 01/31/2022
Number of Avalanches: 2
Location
Location: Mount Emmons
Location Specific:
Start Zone Elevation: BTL: Below Tree Line
Aspect: NE
Characteristics
Trigger: Skier
Trigger modifier: Controlled
Type: Loose
Failure Plane:
Size
Relative Size: R1 very small
Destructive Size: D1- Relatively harmless to people
Avg. crown height (inches):
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Involvements
# of people caught:
# of partial burials:
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Additional comments: Exit of Redwell. Easy to predict, but cold temps continue to weaken deeper into the snowpack.
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5300