Size 2 on Claimstake

Avalanche

peanutbutterman · Feb 6, 2021 · Manning

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Quick report

Weather
cloudy, stormy
Ride Type
cutBlocks, mellowSlopes, convexSlopes, openTrees, alpineSlopes
Stayed Away
steepSlopes
Riding Quality
amazing
Snow Conditions
deepPowder, powder
Avalanche Conditions
avalancheConditionSnow

Great day of skiing and skinning but the significant snowfall made things riskier in open areas, unsupported slopes. Triggered ~size 2 avalanche in alpine terrain just below claimstake summit. Skier 1 triggered over skier 2’s turns while moving across the face. Propagated 30m or so, with runout about 400m, it was storm slab 30cm layer that came off. Everyone safely spread out so no incidents thankfully. Coordinates and time approximate.

Weather

Wind Speed
windSpeedLight
Blowing Snow
moderate
Sky Condition
overcast
Snowfall Rate
2
New Snow24 Hours
30
Temperature Trend
steady
Precipitation Type
snow

Snowy, gusts of wind. Lots of snowfall over the weekend (from Friday to Sunday about 45 cm snowfall).

Snowpack

Depth
2800
Obs Type
point
Site Aspect
S
Test Fracture
resistant
Site Elevation
1500
Ski Penetration
30
Test Initiation
easy
Test Failure Depth
30
Site Elevation Band
tln
Surface Conditions
newSnow
Test Failure Layer Crystal Types
stormSnow

Storm slab came off in 14 hits in column test. No results in other layers. Once in tree-line conditions, we had noticed some pizza-shaped slabs form at the corners of the kick turns on the skinning up (similar to shooting cracks). No whumpfing noticed or 'traditional' shooting cracks propagating into open snow. We made note to not ski over other people's tracks because of this (the avalanche was triggered because skier 1 ended up crossing skier 2's tracks on the way down)

Avalanche

Run Length
300
Slab Width
30
Trigger Type
skier
Wind Exposure
leeSlope
Avalanche Size
2
Slab Thickness
30
Trigger Sub Type
accidental
Start Zone Aspect
SE
Vegetation Cover
openSlope
Start Zone Incline
30
Avalanche Character
stormSlab
Number Of Avalanches
1
Start Zone Elevation
1950
Runout Zone Elevation
1650
Weak Layer Crystal Type
stormSnow
Start Zone Elevation Band
tln, alp
Avalanche Occurrence Datetime
2021-02-06T11:00:00

Skier 1 skied over skier 2's tracks near a convex, alpine slope just above some open trees. Skier 1 triggered the top ~30cm of storm snow which propagated about 30 m. Skier 1 yelled, and Skier 2 was about 200-300m below skier 1 and was able to avoid avalanche run out. The avy ran out about 300m.