Weak Layer

Weak Layer Information

Layer Burial Date:
December 8, 2022
Layer Grain Type (Primary):
SH -Surface Hoar
Layer Grain Type (Secondary):
Comments:

Name: 12/8 Buried Surface Hoar

Author: AH

Zones: East North, West South, Hood, Olympics

Burial Date: West South = 12/8; Hood = ; Olympics = ; East Central 12/8

20221212: Blewett Pass; Tronson Meadows, 12/8 SH buried 18cm, unreactive in stability tests: KW

20221227: ENorth, Cutthroat ck, Shangri-La, 12/8 SH (10.0mm) ↓105cm. Intact, still dry, (despite overlying MF) and indicating propagation after major load from xmas storms. PST 30/100 END, CTH(SC)

 

Media

A profile showing 46cm of new snow over the 12/25 crust and melt forms. The 12/8 surface hoar produced test results indicating potential for propagation, despite the hard, overlying snow.
Results from a propagation saw test indicating that, if initiated, propagation is likely on surface hoar (12/8?). It's now capped with a stout layer of melt forms.
Large, 1cm, surface hoar (12/8?) found about 3 ft below the the surface. Cutthroat ck, SE, 5340ft

Weak Layer Observations

Professional Field Reports:
Dec 29, 2022 - Hairpin Valley
Dec 27, 2022 - Cutthroat creek
Dec 17, 2022 - Hurricane Ridge-Maggies
Dec 17, 2022 - Staircase Trees
Dec 15, 2022 - North Side- Tilly Jane
Dec 13, 2022 - Hogback Mt./ White Pass Backcountry
Avalanche Occurrences:
Dec 27, 2022 - Head of hairpin Valley/ West aspect of Kangaroo
Dec 20, 2022 - Swamp Creek
Dec 10, 2022 - Edith Creek
Dec 11, 2022 - Newton Canyon
Dec 10, 2022 - White Pass Backcountry - 1st Bowl