Whetstone Avalanche (and one from Cement Mountaint) – upper elevations

Date of Observation: 12/25/2021
Name: Eric Murrow

Zone: Southeast Mountains
Route Description: Roadside avalanche obs.

Observed avalanche activity: Yes
Avalanches: Numerous near and above treeline avalanches on northwest through north through east aspects.

Photos:

: Cement Mountain avalanche in northwest-facing bowl.

: Main Bowl avalanches.

: Avalanches on easterly terrain near Whetstone’s centeral hight point

: Multiple naturals in Lucky Boy Basin.

: Several large avalanches in Barcelona Bowl.

Avalanche Report #1

Estimated avalanche date: 12/24/2021
Number of Avalanches: 5

Location

Location: Mount Whetstone
Location Specific:
Start Zone Elevation: ATL: Above Tree Line
Aspect: NE

Characteristics

Trigger: Natural
Trigger modifier:
Type: Soft Slab
Failure Plane:

Size

Relative Size: R2 small
Destructive Size: D2.5
Avg. crown height (inches):
Avg. width (feet):
Avg. vertical run (feet):

Involvements

# of people caught:
# of partial burials:
# of full burials:

Additional comments: Barcelona Bowl, Lucky Boy, M-Face

Avalanche Report #2

Estimated avalanche date: 12/24/2021
Number of Avalanches: 3

Location

Location: Mount Whetstone
Location Specific:
Start Zone Elevation: ATL: Above Tree Line
Aspect: N

Characteristics

Trigger: Natural
Trigger modifier:
Type: Soft Slab
Failure Plane:

Size

Relative Size: R2 small
Destructive Size: D2.5
Avg. crown height (inches):
Avg. width (feet):
Avg. vertical run (feet):

Involvements

# of people caught:
# of partial burials:
# of full burials:

Additional comments: Barcelona, Lucky Boy, Main Bowl

Avalanche Report #3

Estimated avalanche date: 12/24/2021
Number of Avalanches: 1

Location

Location: Mount Whetstone
Location Specific:
Start Zone Elevation: ATL: Above Tree Line
Aspect: E

Characteristics

Trigger: Natural
Trigger modifier:
Type: Soft Slab
Failure Plane:

Size

Relative Size: R2 small
Destructive Size: D3 – could destroy a car, wood-frame house, or snap trees
Avg. crown height (inches):
Avg. width (feet):
Avg. vertical run (feet):

Involvements

# of people caught:
# of partial burials:
# of full burials:

Additional comments: Easterly Fish Bowl off Central Summit of Whetstone – drains into Lucky Boy drainage

Avalanche Report #4

Estimated avalanche date: 12/24/2021
Number of Avalanches: 1

Location

Location: Mount Whetstone
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: D2 – could bury, injure, or kill a person
Avg. crown height (inches):
Avg. width (feet):
Avg. vertical run (feet):

Involvements

# of people caught:
# of partial burials:
# of full burials:

Additional comments: Main Bowl – lookers right side, poor lighting, but did not look to connect to northerly-facing avalanche in Main Bowl

Avalanche Report #5

Estimated avalanche date: 12/24/2021
Number of Avalanches: 3

Location

Location: Mount Whetstone
Location Specific:
Start Zone Elevation: NTL: Near Tree Line
Aspect: NW

Characteristics

Trigger: Natural
Trigger modifier:
Type: Soft Slab
Failure Plane:

Size

Relative Size: R2 small
Destructive Size: D2 – could bury, injure, or kill a person
Avg. crown height (inches):
Avg. width (feet):
Avg. vertical run (feet):

Involvements

# of people caught:
# of partial burials:
# of full burials:

Additional comments: Larry, Moe, and Curly area on northern end of massif

5148