Forecaster Observation - Hash Mountain, Swan Range

Location Name: 
Forecaster Observation - Hash Mountain, Swan Range
Swan Range - East Side (Hungry Horse Reservoir access)
Date and time of observation: 
Fri, 12/18/2015 - 12:30
Location Map: 

Red Flags: 
Whumphing noises, shooting cracks, or collapsing
Recent loading by new snow, wind, or rain

Observation made by: Forecaster
Snowpit Observations
More detailed information about the snowpack: 

This location picked up about 4 inches of new snow overnight and into the morming. Moderate to strong ridgetop winds were drifting new snow and loading leeward slopes. New snow fell on low density cohesionless snow from Tuesday (12/15). This new storm and wind slab was reactive at the interface with 12/15 snow. While traveling along a ridgeline we observed obvious signs of instability including: shooting cracks, collapsing, and triggered 2 soft slab avalanches from above. In our stability tests, we were able to initiate a fracture and it propagated below this storm slab with easy force in an Extended Column Tests (ECTP8). At 6700 feet, the December 9 rain crust was 46 cm from the surface and had weak, faceted snow below. This layer also fractured and propagated across the column with hard force (ECTP 25).

Snowpit or crown profile photo or graph: 
Snowpack photos: 
Snowpit videos (tests, etc): 

December 18, 2015 - Sensitive Wind Slabs in Lost Johnny, Swan Range

Weather Observations
Blowing Snow: 
Cloud Cover: 
100% of the sky covered by clouds
Air temperature: 
Below Freezing
Wind Speed: 
Strong (Whole trees in motion)
Wind Direction: 
Accumulation rate: 
Less than 1 in. per hour
More detailed information about the weather: 

Winds were out of the south at 5-10 in sheltered areas, but gusting in the 30s on exposed ridges.

Precip Rate: 
S1; light snowfall, 1cm/hour
High Temp. (C): 
Low Temp. (C):