Daisy Pass area snow and avi obs

Location: Paradise Divide Area
Date of Observation: 11/06/2018
Name: Eric Murrow

Subject: Daisy Pass area snow and avi obs
Aspect: North, North East, East
Elevation: 9200′ – 11600′


Significant natural avalanche on NE – E aspect in the Martini Couloir off of Mt. Richmond, D2 in size. This slide likely failed sometime on Monday, 11/5, during towards end of snowfall and certainly during windloading event (see photo below). While driving home also noticed a fesh slide in Redwell Basin off of Mt. Emmons. This slide was difficult to view but appeared to be a D1-1.5. It failed on an East aspect sometime during the day on Tuesday 11/6.

Weather: Few clouds with gusty westerly winds. Alpine peaks had steady plumes of snow blowing towards easterly aspects. Most of this snow was being blasted into the atmosphere with minimal loading.
Snowpack: Snow depth across NTL terrain ranged from 20cm to 70cm in general. Terrain we travelled through was very open and “alpine” like even though still in the NTL elevation band. We ascended generally easterly terrain ( NE – E). In the NTL elevation band the snowpack consisted of basal facets ( 5-20cm thick) capped with a crust (1-4cm thick) then this old snow was topped with 10 – 100cm of new snow from the past week. Distribution of this past weeks snow was extremely variable in open terrain. Winds from the past few days blasted the new snow around. Found a few spots of slabby new snow, but mostly thin breaker windboards in open terrain. One location at 11,600 ENE aspect had a drifted area that was well over 100cm deep. We didn’t experience any collapsing or significant cracking (all cracking was limited to thin windboard surfaces). Views of surrounding alpine terrain gave the impression that alpine windloaded features where snowpack was deepest presented the possibility of triggering slab avalanches.