tale of two worlds

Location Name: 
Forecaster Observation - Canyon Creek and southern WF Range
Observation date: 
Saturday, January 12, 2019 - 14:45
Is this an Avalanche Observation: 
No
Observation made by: Forecaster

Location

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Quick Observation

Still winter above ~5500 feet. 

  • No rain crust on surface above ~that elevation
  • Surface hoar developing on shady, cool, mid-elevations slopes
  • Several shallow but relatively long-running loose snow sluffs triggered by sun on southerly slopes ~6300 feet
  • Well-consolidated slab above basal facets in two snow profiles on mid-elevation slopes (sunny, shady)
  • No propagation in snow profile tests or other signs of instability

 

Travel Details
Region: 
Whitefish Range - Southern (south of Coal Creek)
Route Description: 

Canyon Ck trailhead to summit of Big Mtn, out to junction below Werner Peak and return.

Activity: 
Snowmobiling
Snowpack Details
Snowpack and Weather Details: 
Hide Terrain
Elevation of observation: 
3500-5000 ft
5000-6500 ft
Aspect(s) of observation: 
N
NE
E
SW
W
New Snow in the past 24 hours: 
0.00in.
Total Snow Depth: 
150 cm
More comments about the snowpack and weather: 
Valley stratus keeping skies and peaks obscured below ~4500 ft. Partly cloudy above that. Although temps below freezing, direct solar input on sunny slopes moistening surface snow, triggering snow to drop from trees and rocks, rollerballs on upper-elevation slopes, and some shallow but long-running sluffs on slopes steeper than about 40 degrees. 2+ mm upright surface hoar on shady, mid-elevation slopes. In two mid-elevation snow profiles (SW 5700 ft; N 5850 ft), well-consolidated, 115 cm-thick slab (1- and 4-finger small rounds) s over 25-30 cm thick basal facets (4-finger 1.5 mm, moist on SW) and crusts. No propagation in tests; no signs of instability.
Blowing Snow: 
None
Wind Speed: 
Calm (No air motion)
Air temperature: 
Below Freezing
Sky Cover: 
Partly Cloudy (SCT)
Avalanche Details
Avalanche Details: 
Date and Time of Avalanche: 
Saturday, January 12, 2019 - 18:45
Avalanche Type: 
Loose Dry/ Sluff
Failure Plane/Weak Layer: 
New/old snow interface
More information or comments about the avalanche: 

Steep start zones near ridgeline and above valley stratus. 

Hide Trigger
Trigger: 
natural
Hide Terrain
Start Zone Slope Angle: 
40
Aspect: 
South
Starting Elevation: 
6300 ft
Hide Size
Destructive Size: 
D1 Relatively harmless to people.
Relative Size: 
R1 Very Small
Avalanche Length (Vertical Run): 
250ft.
Avalanche Location: