Doin' the Humpty-Hump

Location Name: 
Furlong/Devils Hump
Observation date: 
Sunday, March 10, 2019 - 22:45
Is this an Avalanche Observation: 
Yes
Observation made by: Forecaster

Tabs

Quick Observation

Exploring in the Tranquil Basin area.

  • Triggered one small, thin pocket of drifted snow on an easterly, upper-elevation slope with a ski cut. Did not propagate or run far. 
  • Saw one crown from a natural avalanche below a wildly-cantilevered cornice on a northeasterly, upper-elevation slope. 1-2 days old?
  • Spatially-variable, bullet-hard slabs near highest ridges and peaks. Present near one summit on northeast and east facing slopes; not present on the next. Westerly sides of ridges scoured on one peak; not the next. 
  • Moderate westerly winds were drifting snow early afternoon, but it was primarily surface hoar and facets, so unlikely to form a slab.
  • Best quality snow on sheltered, northerly slopes at mid-elevations. 
Travel Details
Region: 
Flathead Range/Glacier National Park - John F. Stevens Canyon
Route Description: 

Furlong/ Devils Hump/ out Bronze Stairs

Activity: 
Skiing
Snowpack Details
Snowpack and Weather Details: 
Hide Terrain
Elevation of observation: 
3500-5000 ft
5000-6500 ft
Above 6500 ft
Aspect(s) of observation: 
N
NE
E
W
Red Flags: 
Blowing snow
Persistent Weak Layers: 
Surface Hoar
Facets or Faceted Crust
On the surface
New Snow in the past 24 hours: 
0.00in.
More comments about the snowpack and weather: 
-5 at highway in AM; near freezing in PM. Winds picked up during the day, with steady moderate westerly winds by early afternoon at ridges and gusty L-M winds lower. Light to moderate blowing snow, but mostly consisted of large surface hoar or facets (fun to watch) but won't readily form slabs.
Blowing Snow: 
Moderate
Wind Speed: 
Moderate (Small trees sway)
Air temperature: 
Below Freezing
Sky Cover: 
Partly Cloudy (SCT)
Highest Precipitation Rate: 
No Precipitation (NO)
Avalanche Details
Avalanche Details: 
Date and Time of Avalanche: 
Sunday, March 10, 2019 - 12:30
Avalanche Type: 
Soft Slab
Failure Plane/Weak Layer: 
New/old snow interface
More information or comments about the avalanche: 

Obvious small drift on steep slope. Triggered w ski cut. Did not propagate or run far. Much more benign than yesterday's triggered slides. 

Hide Trigger
Trigger: 
skier
Trigger Modifier: 
Intentionally Triggered
Hide Terrain
Start Zone Slope Angle: 
38
Aspect: 
East
Starting Elevation: 
7000
Hide Size
Destructive Size: 
D1 Relatively harmless to people.
Relative Size: 
R1 Very Small
Crown Height: 
Less than 1 ft
Avalanche Length (Vertical Run): 
60ft.
Avalanche Width (Average width): 
15ft.
Hide People Involved
Number of people caught: 
0
Avalanche Location: 
Date and Time of Avalanche: 
Sunday, March 10, 2019 - 23:00
Avalanche Type: 
Soft Slab
Failure Plane/Weak Layer: 
Unknown
More information or comments about the avalanche: 

Below a wildly-overhanging cornice. Looked deeper than a foot in places. Looked fresh within the past 1-2 days.

Hide Trigger
Trigger: 
natural
Hide Terrain
Aspect: 
Northeast
Starting Elevation: 
6800
Hide Size
Destructive Size: 
D1.5
Relative Size: 
R2 Small
Avalanche Length (Vertical Run): 
125ft.
Avalanche Width (Average width): 
80ft.
Hide People Involved
Number of people caught: 
0
Avalanche Location: