Slate River storm snow

CB Avalanche Center2017-18 Observations

Location: Paradise Divide Area
Date of Observation: 03/19/2018
Name: Eric Murrow

Subject: Slate River storm snow
Aspect: North, North East, East
Elevation: 8900′ – 10400′


Many skiers and boarders out testing steep near and below treeline terrain on northerly slopes. Few very small skier triggered loose sloughs of little consequence, and one skier triggered, D2, storm slab avalanche on Schuylkill Ridge (documented in earlier ob). Numerous very small natural loose avalanches in new snow coming out of steep rocky cliff areas near and above treeline.

Weather: Partly cloudy skies with thicker cloud cover moving over the spine of Ruby Range. Light winds at below treeline elevations, vis of above treeline terrain was in and out, but observed no snow transport.
Snowpack: New snow accumulations were 3″ at Slate river TH and increased up 5″ at 10400′. Small isolated drifts below treeline were up to 9″ deep, but no cracking was observed. Terrain that faced NW – NE had dry snow underneath new snow but NE – E had 1-3cm sun crust below new snow (faceting was apparent below the crust, and could be a problem if a significant load is deposited in near future). Also of note – found graupel layer in drifted areas from Friday’s storm(3/16), CT’s produced moderate results on the graupel but no slab present above just low-density storm snow. Graupel layer was not widespread throughout below treeline northerlies limited to terrain features that were drifted after Friday’s storm on terrain features that were slightly tilted to the east.