Avalanche Occurrence

Observer:

NWAC Forecaster

Occurrence Date:

Dec 4, 2022 ()

Location:

Table Mt. - Austin Pass

Comments:

From Public Ob 12/5/22 . . . . single rider triggered, caught and carried to bottom of slope. Surrounding terrain heavily travelled but unknown if anybody had specifically been in this section of terrain prior to incident.

Triggered from below crown - wide propagation above and away from the rider. Weak layer observed as 1mm facets ↓130cm sitting on K melt-freeze crust.

# of Avys:

1

Aspect:

NW

Start Zone Elev:

4800ft

Size:

D2 / R4

Type:

HS-Hard Slab

Trigger:

AR-Snowboarder
u-Unintentional

Bed Surface:

O-Old Snow

Depth:

4.5ft

Width:

130ft

Start Zone Slope:

41°

Vertical Fall:

250ft

Steep, tracked out avalanche terrain drifting in with wind blown snow.

View from the debris to the crown of same avalanche. The person who triggered it was quite lucky to ride away without injury.

These 1mm weak, faceted grains were the weak layer in a recent human triggered avalanche in the Baker Backcountry. They developed above a hard crust which ended up being the bed surface.