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Oodles and oodles of fracture lines
Location Name:
Flathead Range
Observation date:
Friday, January 15, 2021 - 21:00
Is this an Avalanche Observation:
Yes
Observation made by:
Forecaster
Tabs
Quick Observation
We enjoyed a day off gazing at avalanches from the 1/12-13 storm
An impressive storm slab avalanche cycle occurred during the potent storm.
One fracture line was over 1000' in length.
The sheer number of fracture lines dwarfed the smallish debris piles.
The debris piles from the 12/22 Solstice storm were much larger than those from this past storm. This may be due to the lack of snow left in these paths, especially the south-facing.
Snowpack, Avalanche, Weather Images:
Snowpack Details
Snowpack and Weather Details:
Terrain
Elevation of observation:
3500-5000 ft
Aspect(s) of observation:
N
NE
E
Red Flags:
Avalanches from the past 2 days
New Snow in the past 24 hours:
1.00in.
More comments about the snowpack and weather:
The crust thickened with elevation and was not supportable on skis to our high point of 5000.'
Air temperature:
Below Freezing
Snow line:
4000'
Avalanche Details
Avalanche Details:
Date and Time of Avalanche:
Wednesday, January 13, 2021 - 00:00
Number of avalanches:
6
Avalanche Type:
Soft Slab
Failure Plane/Weak Layer:
Within storm snow
Trigger
Trigger:
natural
Terrain
Start Zone Slope Angle:
35
Aspect:
Northeast
Starting Elevation:
near-treeline
Size
Destructive Size:
D2 Could bury, injure, or kill a person.
Relative Size:
R3 Medium
Crown Height:
1 ft
Avalanche Length (Vertical Run):
800ft.
Avalanche Width (Average width):
100ft.
Avalanche Location:
Javascript is required to view this map.
Date and Time of Avalanche:
Wednesday, January 13, 2021 - 00:45
Number of avalanches:
1
Avalanche Type:
Soft Slab
Failure Plane/Weak Layer:
Within storm snow
Trigger
Trigger:
natural
Terrain
Start Zone Slope Angle:
40
Aspect:
North
Starting Elevation:
near-treeline
Size
Destructive Size:
D2.5
Relative Size:
R3 Medium
Crown Height:
1 ft
Avalanche Length (Vertical Run):
900ft.
Avalanche Width (Average width):
100ft.
Avalanche Location:
Javascript is required to view this map.
Date and Time of Avalanche:
Wednesday, January 13, 2021 - 00:45
Number of avalanches:
1
Avalanche Type:
Soft Slab
Failure Plane/Weak Layer:
Within storm snow
Trigger
Trigger:
natural
Terrain
Start Zone Slope Angle:
35
Aspect:
Northeast
Starting Elevation:
near-treeline
Size
Destructive Size:
D2 Could bury, injure, or kill a person.
Relative Size:
R4 Large
Crown Height:
1 ft
Avalanche Length (Vertical Run):
300ft.
Avalanche Width (Average width):
1200ft.
Avalanche Location:
Javascript is required to view this map.
Date and Time of Avalanche:
Wednesday, January 13, 2021 - 00:15
Number of avalanches:
20
Avalanche Type:
Soft Slab
Failure Plane/Weak Layer:
Within storm snow
Trigger
Trigger:
natural
Terrain
Start Zone Slope Angle:
35
Aspect:
East
Starting Elevation:
near-treeline
Size
Destructive Size:
D1.5
Relative Size:
R2 Small
Crown Height:
1 ft
Avalanche Length (Vertical Run):
250ft.
Avalanche Width (Average width):
75ft.
Avalanche Location:
Javascript is required to view this map.
Date and Time of Avalanche:
Wednesday, January 13, 2021 - 00:15
Number of avalanches:
10
Avalanche Type:
Soft Slab
Failure Plane/Weak Layer:
Within storm snow
Trigger
Trigger:
natural
Terrain
Start Zone Slope Angle:
35
Aspect:
Southeast
Starting Elevation:
near-treeline
Size
Destructive Size:
D1.5
Relative Size:
R3 Medium
Crown Height:
1 ft
Avalanche Length (Vertical Run):
250ft.
Avalanche Width (Average width):
75ft.
Avalanche Location:
Javascript is required to view this map.
