Sawtooth Avalanche Center

Avalanche Occurrence

View Associated Field Report

General Information

Multiple avalanches that released on Copper Mountain in the Banner Summit Zone. These broke 1.5-2' deep on the facet layer that formed during the Nov/Dec dry spell. 8600-8700', E-NE.

Observer:
SAC Forecaster

Verified by SAC?
Yes

Occurrence Date:
Dec 21, 2020 (+/- 1 day)

Location:
Bowl south of Copper Mtn

Comments:

Numerous avalanches observed, exact count is uncertain due to mediocre visibility. Essentially anything over 35 degrees ran. Avalanches occurred along the upper elevation ridge crest as well as mid-slope/mid-elevation rollovers.

Avalanche Characteristics

# of Avys:
10
Aspect:
NE (E,NE,N)
Start Zone Elev:
8700ft
Size:
D2
Type:
SS-Soft Slab
Trigger:
N-Natural
Bed Surface:
O-Old Snow
Depth:
1.5ft (max: 2ft)
Weak Layer:
Dec 11, 2020 (FCsf)
Comments:

Avalanche size ranged from D1-2, size generally dictated by scale of terrain.

Media

Multiple avalanches that released on Copper Mountain in the Banner Summit Zone. These broke 1.5-2' deep on the facet layer that formed during the Nov/Dec dry spell. 8600-8700', E-NE.
Natural avalanche that broke 20-24" deep near Copper Mountain in the Banner Summit zone. 8800', NE.