Sluff the magic dragon

Location Name: 
Forecaster Observation - Flathead Range
Observation date: 
Monday, February 10, 2020 - 17:15
Is this an Avalanche Observation: 
Yes
Observation made by: Forecaster

Location

Tabs

Quick Observation

In today’s tour at middle elevations in the Middle Fork, we easily triggered small sluffs but could not find any signs of slab instabilities.

  • 2” to 3” of new snow overnight without any evidence of wind transport apart from a few small plumes near high summits.
  • We traveled past numerous 6”-12” crowns that ran on Saturday, but could not produce any cracking or signs of instability in similar terrain features today.
  • We skied steep slopes up to 45 degrees and triggered numerous sluffs in the top few inches of the snow. In sustained steep pitches, the sluffs entrained snow down to the 2/1 crust and grew to D1.5 in size. We managed these instabilities using sluff management techniques.
  • We had good views of a lot of terrain and could not see any fresh slab avalanches. We observed a handful of D1 to D1.5 natural sluffs that ran today at mid and upper elevations.
Snowpack, Avalanche, Weather Images: 
Travel Details
Region: 
Flathead Range - Middle Fork Corridor
Route Description: 

To 6000'

Activity: 
Skiing
Snowpack Details
Snowpack and Weather Details: 
Hide Terrain
Elevation of observation: 
3500-5000 ft
5000-6500 ft
Aspect(s) of observation: 
E
SE
NW
Persistent Weak Layers: 
Facets or Faceted Crust
Buried
New Snow in the past 24 hours: 
3.00in.
More comments about the snowpack and weather: 
Clouds decreased from overcast to broken overhead. Scattered clouds looking north.
Blowing Snow: 
None
Wind Speed: 
Calm (No air motion)
Air temperature: 
Below Freezing
Snow line: 
Valley
Sky Cover: 
Mostly Cloudy (BRK)
Highest Precipitation Rate: 
Very Light Snowfall (S-1)
Avalanche Details
Avalanche Details: 
Date and Time of Avalanche: 
Monday, February 10, 2020 - 12:30
Number of avalanches: 
7
Avalanche Type: 
Loose Dry/ Sluff
Failure Plane/Weak Layer: 
Within storm snow
More information or comments about the avalanche: 

Mostly D1. A couple D1.5. Ran faster and further than yesterday due to the fluffy new snow overnight 

Hide Trigger
Trigger: 
skier
Hide Terrain
Starting Elevation: 
near-treeline
Hide Size
Destructive Size: 
D1 Relatively harmless to people.
Relative Size: 
R1 Very Small
Avalanche Length (Vertical Run): 
300ft.
Avalanche Location: 
Date and Time of Avalanche: 
Monday, February 10, 2020 - 12:30
Number of avalanches: 
3
Avalanche Type: 
Loose Dry/ Sluff
Failure Plane/Weak Layer: 
Within storm snow
More information or comments about the avalanche: 

Nyack face

Hide Trigger
Trigger: 
natural
Hide Terrain
Starting Elevation: 
above-treeline
Hide Size
Destructive Size: 
D1.5
Relative Size: 
R1 Very Small
Avalanche Length (Vertical Run): 
500ft.
Avalanche Location: