Clamshell remote cornice sz 2.5+

Quick report

Weather

cloudy, sunny

Ride Type

alpineSlopes, mellowSlopes, openTrees, sunnySlopes

Stayed Away

convexSlopes, steepSlopes

Riding Quality

good

Snow Conditions

powder

Avalanche Conditions

avalancheConditionSlab

Went up and down the low angle supported SE shoulder of the Clamshell. On the final approach to the summit, the second person on the skin track heard a deep low pitch noise on the north side of the shoulder but could not see any sign from its location. On the way down the shoulder, it was noticed that approximately 200m long of cornice had failed and triggered the persistent slab sitting on the Feb 3 crust. The remote trigger distance was estimated at 20m. It was impossible to see how far down the north face the resulting avalanche had ran but given the terrain, it likely ran over 500m vert.

Avalanche

Slab Width

200

Trigger Type

skier

Wind Exposure

leeSlope

Avalanche Size

2.5

Slab Thickness

60

Trigger Sub Type

remote

Start Zone Aspect

N

Trigger Distance

20

Vegetation Cover

openSlope

Start Zone Incline

45

Avalanche Character

corniceWithSlab, persistentSlab

Crust Near Weak Layer

1

Number Of Avalanches

1

Start Zone Elevation

2550

Weak Layer Burial Date

2024-02-03

Weak Layer Crystal Type

facets

Start Zone Elevation Band

alp

Avalanche Occurrence Datetime

2024-03-04T19:00:00.000Z