Weak Layer

Comments:

Name: 3/8 Facets, often found above the Early March Crust

Author: DG

Zones: WN, WC, WS, STV, SNQ, EN, HD, EC, ES             OLY?

Comments:

20220310: SNQ, DG: 1-1.5mm FC found above the Early March crust and under the snow from the 8th. FCs only found on NW-NE aspects. Noticeably absent on southerly slopes. Still very shallow only 5-10cm below the surface on most slopes.

20220311: WS: Crystal: DG: Very similar to the set up at SNQ, 1-1.5mm facets found in Cache, Powder Pass, Silver Basin. NW-NW aspects about 5-8cm below the surface. Surface was getting moist even on shaded slopes, but FC remained very dry and weak.

20220313: STV, MP: ~4cm over the early March crust, with 1mm FC from 4,500-5,000ft on NW-NE. 5-6k found 8cm or so, with 4cm of that from prior to the 8th at F hardness 1.5-2mm FC, and 4cm newer snow (DF,FCxr). Above 6k FC to 2mm exist above the early March crust, often harder than 4F-, often buried beneath small pockets of P hard windslab. Direct, steep S were melted to old MF crust, but ESE held dry snow and likely FC. Added EC to the mix as KW observed large, striated FC on the 6th on BTL shaded slopes nr crest.

20220318: ES, AK: 30cm over 1-1.5mm FCxr above Early March Crust. This structure exists above 5500-6000ft on E-N-W aspects. The weak layer appears to only be reactive where thicker/stiffer slabs rest above in wind-loaded N-E aspects. Compression tests, shovel-tilt tests, and hand shears produced SP and RP results with moderate force. No propagation in large column tests.