Date of Observation: 02/23/2023
Name: Eric Murrow
Zone: Southeast Mountains
Route Description: Hwy 135 obs and tour up sunny side of Mount Emmons.
Observed avalanche activity: Yes
Avalanches: While driving to town I got a glimpse of a few naturals in drifted terrain on Whetstone that appeared to only involve the storm snow. Slides pictured are from the Octagon zone (D1.5) and Barcelona Bowl (D2-ish). Brief glimpse of Main Bowl and Hidden Lake basin suggested more activity but the views were too brief to really see what happened.
On Emmons, I observed a few D1.5 naturals in the drifted terrain below the skinner near treeline but never was able to see the crowns below the cornice.
Weather: Cold temps were tolerable at the valley bottom and decreased to unpleasant levels above treeline. Winds above treeline were commonly light to moderate with an occasional strong gust. Snowfall was very light from 10 am to 3 pm, with less than an inch of accumulation. Some snow transport was observed midday loading into easterly terrain.
Snowpack: Storm totals ranged from 10 to 14 inches. In sheltered areas, I did not get any cracking in the storm snow and a test profile site from a northeast feature produced no propagating results in the upper 3 feet of the snowpack. Once I started to find drifted snow near and above treeline, I was able to reliably get cracks to shoot 10 feet but much less reactive than Wednesday. Stomping above and kicking cornices into drifted terrain did not produce any results.
Photos:
-
-
Natural avalanche in the storm snow from an easterly near treeline zone.
-
-
Natural involving drifted storm snow in Barcelona Bowl.
Estimated avalanche date: 02/22/2023
Number of Avalanches: 2
Location
Location: Mount Emmons
Location Specific:
Start Zone Elevation: NTL: Near Tree Line
Aspect: NE
Characteristics
Trigger: Natural
Trigger modifier:
Type: Soft Slab
Failure Plane: Within storm snow
Size
Relative Size: R2 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: Below corniced ridgeline mid-skinner.
Estimated avalanche date: 02/22/2023
Number of Avalanches: 1
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: New/Old interface
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: Barcelona Bowl
Estimated avalanche date: 02/22/2023
Number of Avalanches: 1
Location
Location: Mount Whetstone
Location Specific:
Start Zone Elevation: NTL: Near Tree Line
Aspect: E
Characteristics
Trigger: Natural
Trigger modifier:
Type: Soft Slab
Failure Plane: New/Old interface
Size
Relative Size: R2 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: Octagon area across from CB south.
6034