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Not today
Location Name:
Flathead Range
Observation date:
Tuesday, April 21, 2020 - 14:00
Is this an Avalanche Observation:
Yes
Observation made by:
Public
Location
Tabs
Quick Observation
Warm overnight temperatures resulted in a wet and mushy snow surface. Northerlies had a foot of wet snow on top of a crust at low and mid-elevations. Rollerballs and wet loose slides were easy to initiate in steep terrain. Low angle sunny slopes offered decent push the mush turns.
Wet loose activity was noted on both south and north aspects from the weekend storm. Slides were generally D1.5 with a couple of D2 that entrained snow lower in the path. Natural wet loose activity occurred intermittently on south slopes through my noon departure time.
The forested approach and egress is dirty with logs and brush emerging.
Snowpack, Avalanche, Weather Images:
Travel Details
Region:
Flathead Range - Middle Fork Corridor
Route Description:
Activity:
Skiing
Snowpack Details
Snowpack and Weather Details:
Terrain
Elevation of observation:
3500-5000 ft
5000-6500 ft
Aspect(s) of observation:
N
NE
E
SE
Red Flags:
Avalanches from the past 2 days
Rollerballs / pinwheels
Persistent Weak Layers:
Not observed
New Snow in the past 24 hours:
0.00in.
Air temperature:
Above Freezing
Snow line:
7000'
Sky Cover:
Mostly Clear (FEW)
Avalanche Details
Avalanche Details:
Date and Time of Avalanche:
Monday, April 20, 2020 - 12:15
Number of avalanches:
2
Avalanche Type:
Wet Loose
Failure Plane/Weak Layer:
Within storm snow
More information or comments about the avalanche:
Trigger
Trigger:
natural
Terrain
Start Zone Slope Angle:
35
Aspect:
Southeast
Starting Elevation:
near-treeline
Size
Destructive Size:
D2 Could bury, injure, or kill a person.
Relative Size:
R2 Small
Avalanche Length (Vertical Run):
1000ft.
Avalanche Width (Average width):
50ft.
Avalanche Location:
Javascript is required to view this map.
Date and Time of Avalanche:
Monday, April 20, 2020 - 12:00
Number of avalanches:
5
Avalanche Type:
Wet Loose
Failure Plane/Weak Layer:
Within storm snow
More information or comments about the avalanche:
Trigger
Trigger:
natural
Terrain
Start Zone Slope Angle:
40
Aspect:
Southeast
Starting Elevation:
near-treeline
Size
Destructive Size:
D1.5
Relative Size:
R2 Small
Avalanche Length (Vertical Run):
300ft.
Avalanche Width (Average width):
30ft.
Avalanche Location:
Javascript is required to view this map.
Date and Time of Avalanche:
Monday, April 20, 2020 - 12:00
Number of avalanches:
4
Avalanche Type:
Wet Loose
Failure Plane/Weak Layer:
Within storm snow
More information or comments about the avalanche:
Trigger
Trigger:
natural
Terrain
Start Zone Slope Angle:
35
Aspect:
Northeast
Size
Destructive Size:
D1.5
Relative Size:
R2 Small
Avalanche Length (Vertical Run):
200ft.
Avalanche Width (Average width):
40ft.
Avalanche Location:
Javascript is required to view this map.
