Forecaster Observation - Kimmerly Basin, southern Whitefish Range

Location Name: 
Forecaster Observation - Kimmerly Basin, southern Whitefish Range
Region: 
Whitefish Range - Southern (south of Coal Creek)
Date and time of observation: 
Tue, 02/28/2017 - 12:00
Location Map: 

Red Flags: 
Recent loading by new snow, wind, or rain
Observation made by: Forecaster
Snowpit Observations
More detailed information about the snowpack: 

We traveled to Kimmerly Basin in the southern Whitefish Range to assess recent storm instabilities. We found 18-20 inches of unconsolidated snow on the road to Kimmerly basin. Off road there were nearly 4 feet of light snow on top of the Feb. 10th crust. Both riding and skiing conditions were phenomenal. Breaking trail to the ridgeline was arduous due to the deep snow and we observed a few localized cracks in the snow surface when crossing steep terrain features.

Along the ridgeline the light southwest wind was easily drifting the light snow and forming soft wind slabs on leeward slopes. We dug a snow pit on a northeast aspect at 6900 feet and found an unstable storm/wind slab near the ridge. In three tests the top 35 cm (14 inches) fractured and propagated across the column with easy force. It was difficult to discern hardness changes in the upper snow pack since the changes are so subtle, but this soft slab fractured on an even less dense layer of snow. In the afternoon as we were leaving the area the winds were increasing and drifting the snow farther down the slope. Our deep skin track was completely filled in in about 30 minutes.

In the short period of partial clearing we witnessed a very small, natural wind slab that occurred on an adjacent ridgeline.  The crown width was estimated at 10 feet wide and about 1 foot deep. This cohesive slab was confined to the ridgeline but entrained a substantial amount of loose snow as it moved down the slope.

Snowpit or crown profile photo or graph: 
Snowpack photos: 
Weather Observations
Blowing Snow: 
Yes
Cloud Cover: 
75% of the sky covered by clouds
Air temperature: 
Below Freezing
Wind Speed: 
Light (Twigs in motion)
Precipitation: 
Snow
Air temperature trend: 
Static
Wind Direction: 
Southwest
Accumulation rate: 
Less than 1 in. per hour
More detailed information about the weather: 

Variable weather conditions through out the day. Sky condition ranged from a few breaks and a bit of sun to obscured. Also, a few squalls moved into the area that brought a wide range of snow intensities up to 1 inch per hour. Southwest winds were 3-7 with gusts to 10 mph early and increased to 10-15 gusting to 20 mph.

Activity: 
Skiing
Precip Rate: 
S1; light snowfall, 1cm/hour
High Temp. (C): 
-8
Low Temp. (C): 
-10