Date of Observation: 11/25/2021
Name: Eric Murrow
Zone: Northwest Mountains
Route Description: Purple ridge area. Ascended and descended through east and northeasterly terrain from 9,600 – 11,800 feet.
Observed avalanche activity: Yes
Avalanches: Observed a couple of natural avalanches that likely ran on Wednesday 11/24. Slab avalanches were above treeline in drifted terrain facing east or southeast. Appeared to only involve the most recent storm snow.
Weather: Beautiful Thanksgiving day. Temperatures rebounded quickly in the AM and winds remained light even at treeline on an exposed ridge. Storm total from the previous day was around 8 inches.
Snowpack: While traveling around a drifted easterly ridgeline, I found mostly soft drifts up to 18 inches thick. Did not experience any cracking or collapsing, but I avoided suspect terrain features with the most significant drifting. On easterly slopes near treeline, the recently drifted storm snow was resting on a fairly soft, 1-2cm melt/freeze crust. This crust was resting on fist-hard, faceted snow. A generally poor-looking structure particularly if you found a slope with a thick drift resting above. While descending below treeline I traveled through northeasterly terrain looking to see if I could produce Dry Loose avalanches but the storm snow has not faceted enough yet to produce any significant sluffing.
Photos:
-
-
Slab avalanche on an easterly aspect on Purple Ridge. Likely ran 11/24.
-
-
Hard to see crowns well as winds buffed the face out, but it appeared like several slabs failed on the east face of Mineral Point. Likely ran 11/24.
-
-
Recent slab on southeast face of Augusta. Likely ran on 11/24.
[/gravityforms]
Estimated avalanche date: 11/24/2021
Number of Avalanches: 3
Location
Location: Poverty Gulch (Pittsburg, Augusta, Baxter Basin)
Location Specific:
Start Zone Elevation: ATL: Above Tree Line
Aspect: E
Characteristics
Trigger: Natural
Trigger modifier:
Type: Soft Slab
Failure Plane:
Size
Relative Size: R1 very small
Destructive Size: D1.5
Avg. crown height (inches):
Avg. width (feet):
Avg. vertical run (feet):
Involvements
# of people caught:
# of partial burials:
# of full burials:
Additional comments: Avalanches from Mineral Point and Purple Ridge
Estimated avalanche date: 11/24/2021
Number of Avalanches: 1
Location
Location: Poverty Gulch (Pittsburg, Augusta, Baxter Basin)
Location Specific:
Start Zone Elevation: ATL: Above Tree Line
Aspect: SE
Characteristics
Trigger: Natural
Trigger modifier:
Type: Soft Slab
Failure Plane:
Size
Relative Size: R1 very small
Destructive Size: D1.5
Avg. crown height (inches):
Avg. width (feet):
Avg. vertical run (feet):
Involvements
# of people caught:
# of partial burials:
# of full burials:
Additional comments: SE face of Augusta Mountain
Estimated avalanche date:
Number of Avalanches:
Location
Location:
Location Specific:
Start Zone Elevation:
Aspect:
Characteristics
Trigger:
Trigger modifier:
Type:
Failure Plane:
Size
Relative Size:
Destructive Size:
Avg. crown height (inches):
Avg. width (feet):
Avg. vertical run (feet):
Involvements
# of people caught:
# of partial burials:
# of full burials:
Additional comments:
Estimated avalanche date:
Number of Avalanches:
Location
Location:
Location Specific:
Start Zone Elevation:
Aspect:
Characteristics
Trigger:
Trigger modifier:
Type:
Failure Plane:
Size
Relative Size:
Destructive Size:
Avg. crown height (inches):
Avg. width (feet):
Avg. vertical run (feet):
Involvements
# of people caught:
# of partial burials:
# of full burials:
Additional comments:
Estimated avalanche date:
Number of Avalanches:
Location
Location:
Location Specific:
Start Zone Elevation:
Aspect:
Characteristics
Trigger:
Trigger modifier:
Type:
Failure Plane:
Size
Relative Size:
Destructive Size:
Avg. crown height (inches):
Avg. width (feet):
Avg. vertical run (feet):
Involvements
# of people caught:
# of partial burials:
# of full burials:
Additional comments:
5031
