Zoa North Slopes

Avalanche

Run Length

150

Slab Width

20

Trigger Type

skier

Wind Exposure

crossLoadedSlope

Avalanche Size

1.5

Slab Thickness

60

Trigger Sub Type

accidental

Start Zone Aspect

NE

Vegetation Cover

sparseTrees

Start Zone Incline

40

Avalanche Character

stormSlab

Number Of Avalanches

1

Start Zone Elevation

1700

Runout Zone Elevation

1675

Weak Layer Burial Date

2025-01-31

Avalanche Observation

24to48hrsAgo

Start Zone Elevation Band

tln

Avalanche Occurrence Datetime

2025-02-02T23:00:00.000Z

Skier unintentionally triggered small slab (crown 15 cm, ~5 m wide) that subsequently triggered a larger slab (up to 60 cm deep, 20 m wide) on the lee side (NE) of a bulge. The slab broke on a small but steep convex slope that appeared to be mostly unsupported below the roll over where the coverage was thin, note exposed rocks and ice. The avalanche ran on a firm bed surface, specifically a firm but breakable series of crusts (1F - P) that developed during the two week dry period. The storm slab stepped down and released another thin slab (10 cm) within the series of crusts. These crusts consist of a combination of melt/freeze crusts that are somewhat bonded and characterized by variation across subtle changes in aspect. The resulting debris was fairly soft and compressible under foot. In all, the avalanche revealed features of the snowpack very much consistent with the results of a compression test nearby. This avalanche, lacking a cohesive slab, remained isolated to a small terrain feature but future loading and larger terrain features, alpine bowls and other open slopes, could become increasingly prone to larger avalanches.