Natural Persistent Slab

Name: Evan Ross
Title: Natural Persistent Slab
Location: Paradise Divide Area
Date of Observation: 11/28/2014
Aspect: South East
Elevation: 9,800-11,800

Weather: Mostly clear sky, calm winds with a few gusts at ridgeline and air temperature near or above 40 degrees.

Snowpack: Many slopes from south east to south to west had a moist snow surface at all elevations traveled.. The snow surface has seen lots of settlement over the last few days and become much more dense. Even on a north facing slope at 10,500ft with dense trees where ski penetration was around 10-20cm.

No instabilities were observed on a 36 degree south slope while traveling and skiing around 11,000ft. See attached snowpit profile below.

Avalanches: Observed 2 natural persistent slabs that failed on the 11/22 interface, around noon on south eastern slopes with crown elevations at 11,800ft.

SS-N-R2-D2-O. Crown width about 300ft wide averaging 12 inches deep. See attached profile and pictures below.

SS-N-R1-D2-O. Crown width about 80ft wide averaging 12 inches deep.

Pit dug on a similar slope and elevation to a natural avalanche on 11/28/14. SS-N-R2-D2-O. (Click title to see Profile)

The weak layer. 2mm facets on a 1cm crust.

Natural persistent slab avalanche that failed on the 11/22 interface, around noon on a south eastern slope with crown elevation at 11,800ft. Crown width about 300ft wide averaging 12 inches deep. SS-N-R2-D2-O.