Naturals, remote triggers, and forecasters tackled by wind slabs, Oh My!
Location Name: Forecaster Observation - Flathead Range Observation date: Saturday, February 8, 2020 - 19:30 |
Is this an Avalanche Observation: Yes |
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Observation made by: Forecaster
Tabs
Avalanche Details:
Date and Time of Avalanche:
Saturday, February 8, 2020 - 11:00
Number of avalanches:
3
Avalanche Type:
Soft Slab
Failure Plane/Weak Layer:
Unknown
Trigger:
natural
Aspect:
Northeast
Starting Elevation:
above-treeline
Destructive Size:
D2 Could bury, injure, or kill a person.
Avalanche Location:
Date and Time of Avalanche:
Saturday, February 8, 2020 - 13:30
Number of avalanches:
3
Avalanche Type:
Soft Slab
Failure Plane/Weak Layer:
New/old snow interface
More information or comments about the avalanche:
Wind slabs triggered by cornice drops, ski cuts, etc. One was remotely triggered. These all failed on small NSF a few inches above the 2/1 crust.
Trigger:
skier
Trigger Modifier:
Intentionally Triggered
Aspect:
East
Starting Elevation:
near-treeline
Destructive Size:
D1.5
Relative Size:
R2 Small
Crown Height:
1 ft
Avalanche Location:
Date and Time of Avalanche:
Saturday, February 8, 2020 - 14:30
Number of avalanches:
1
Avalanche Type:
Soft Slab
Failure Plane/Weak Layer:
New/old snow interface
More information or comments about the avalanche:
Failed on NSF above 2/1 crust.
Trigger:
skier
Trigger Modifier:
Cornice Fall Triggered
Aspect:
East
Starting Elevation:
near-treeline
Destructive Size:
D2 Could bury, injure, or kill a person.
Relative Size:
R2 Small
Avalanche Length (Vertical Run):
800ft.
Avalanche Width (Average width):
1ft.
Avalanche Location:
Date and Time of Avalanche:
Saturday, February 8, 2020 - 13:00
Number of avalanches:
5
Avalanche Type:
Soft Slab
Failure Plane/Weak Layer:
Within storm snow
More information or comments about the avalanche:
A handful of D1 to 1.5's ran during period of increased wind speeds mid day.
Trigger:
natural
Starting Elevation:
near-treeline
Destructive Size:
D1.5
Relative Size:
R1 Very Small
Crown Height:
Less than 1 ft
Avalanche Location:
Date and Time of Avalanche:
Saturday, February 8, 2020 - 12:30
Number of avalanches:
1
Avalanche Type:
Soft Slab
Failure Plane/Weak Layer:
New/old snow interface
More information or comments about the avalanche:
Small rollover, while ascending. Slab broke higher than expected and carried me a few yards.
Trigger:
skier
Trigger Modifier:
Accidentally Triggered
Starting Elevation:
near-treeline
Destructive Size:
D1 Relatively harmless to people.
Relative Size:
R1 Very Small
Crown Height:
1 ft
Avalanche Length (Vertical Run):
15ft.
Avalanche Width (Average width):
20ft.
Number of people caught:
1
Number of partial burials:
0
Number of full burials:
0
Avalanche Location:
Date and Time of Avalanche:
Saturday, February 8, 2020 - 14:30
Number of avalanches:
5
Avalanche Type:
Loose Dry/ Sluff
Failure Plane/Weak Layer:
Within storm snow
More information or comments about the avalanche:
Sluffing in steep, wind protected terrain at mid and low elevations.
Trigger:
skier
Starting Elevation:
near-treeline
Destructive Size:
D1 Relatively harmless to people.
Relative Size:
R1 Very Small
Avalanche Location:
Observed from a distance, on Nyack