Fraser

Snowpack

kirstie · Dec 18, 2016 · White Pass West

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Quick report

Weather
cloudy
Ride Type
mellowSlopes
Stayed Away
steepSlopes, alpineSlopes
Riding Quality
good
Snow Conditions
powder
Avalanche Conditions
avalancheConditionSound, avalancheConditionSlab

AST 1 course at Fraser. Lots of groups in area and sled activity on the NE facing slopes above the creek. Weather had warmed significantly. Conditions continuing to change. We observed wind loading in gullies and significant wind transport in the alpine with many of these alpine areas blown clear of snow. The lookers left of the big gully observable from the quarry had released. Overall, based on our snow and weather observations of the day we were concerned about the potential for soft slab avalanches in steeper sheltered terrain and the potential for releases to ground in the high alpine due to potential for wind slabs releasing on depth hoar in thin snow packs.

Weather

Avg Temp
-6
Max Temp
-6
Min Temp
-23
Wind Speed
windSpeedLight
Sky Condition
overcast
Snowfall Rate
1
Wind Direction
SW
New Snow24 Hours
2
Storm Snow Amount
2
Temperature Trend
rising
Precipitation Type
snow
Precipitation24 Hours
2

winds were increasing as we left and snow accumulation increased to about 1 cm/ hr.

Snowpack

Depth
100
Obs Type
point
Site Aspect
SE
Test Fracture
sudden
Site Elevation
1080
Ski Penetration
20
Test Initiation
easy
Foot Penetration
50
Cracking Observed
1
Test Failure Depth
20
Site Elevation Band
tln
Surface Conditions
crust
Test Failure Layer Crystal Types
surfaceHoar

We traveled up the ridge to the east of fraser creek. Trail breaking through about 20 cms unconsolidated snow through the trees. When we popped out into more exposed areas we observed a wind effect on the surface snow and shooting cracks. We did 2 snow profiles and made 6 observations. Location was sheltered from the wind. Results consistent across all 6. Snow depth average in one pit 92 cms and in second was 102. Ground was wet and just above 0. Slope incline was 14 degrees and 22 degrees. We found a small wind crust of 4 cms that reacted in compression tests on average a compression test (CT) moderate 1. We found 2 surface hoar (SH) layers - on average at about 10 and 20 cms down. The 10 cm SH layer failed at CT Easy 2 and the 20 cm SH layer failed at a CT moderate 4. A Rutchblock ski test resulted in a Rb 4 on the 20 cm SH layer. We observed a 20 cm depth hoar layer but there was ice in it and it did not react. Because we were in a sheltered area this surface hoar layer may be better preserved than in a more exposed location. We noted that there may be pockets of this surface hoar in sheltered areas at this elevation band.