Week in Review for 12/1/2017 - 12/8/2017

Dates of the Week: 
12/1/2017 to 12/8/2017
Avalanche Problems: 
General Snowpack Structure: 
  • Hard wind slabs of variable thickness on top of older near surface facets near and above treeline interspersed with scoured areas. Wind slabs most prominent on NW aspects.
  • Wind scoured surfaces in areas exposed to NE wind events.
  • Lingering unconsolidated storm snow in areas of shade and NE wind protection.
  • Some areas of well developed near surface facets remain near the snow surface on northerly aspects.
  • Melt-freeze surface conditions on solar aspects.
Weather Events: 
  • Storm event on Dec 2-3
  • Very strong high pressure building since storm event.
  • Gale force NE winds on Dec 4-5

Observations From the Past 7 Days

Location Region Date and time of observation or avalanche occurrence Observation Type Avalanche observation video Avalanche photos Snowpit videos (tests, etc) Snowpack photos Snowpit or crown profile photo or graph Observation made by
West side Relay Peak Mount Rose Area 12/14/2017 - 16:00 Snowpack Observation Public
Andesite Peak and S aspect of Castle Pk Donner Summit Area 12/14/2017 - 11:00 Snowpack Observation Forecaster
Castle Peak Donner Summit Area 12/13/2017 - 15:27 Avalanche Observation Public
Chickadee Ridge Mount Rose Area 12/13/2017 - 12:00 Snowpack Observation  Inversion conditions allowing cold air and clouds to remain trapped at the lower elevations. 1 inch of soft wet corn snow on top of a supportable melt-freeze crust on a S aspect at 8850 ft. around 11:30 am. Near-surface facets from a north aspect at 9000 ft. that are starting to round. Forecaster
Andesite Peak Donner Summit Area 12/13/2017 - 11:30 Snowpack Observation Pit location adjacent to and above pit from Dec 6. (Skis/pack in old pit.) Forecaster
Basin Peak Donner Summit Area 12/12/2017 - 11:30 Snowpack Observation thermometer showing +9c Public
Castle Peak Donner Summit Area 12/11/2017 - 13:00 Snowpack Observation ECTP on a NW test slope with a hard wind slab. See pit for more details. ECTN on the same test slope. See pit for more details. Spring-like snow conditions and patchy snow coverage on SW aspects. Scoured surfaces on exposed northerly aspects. Forecaster
East Ridge Tamarack Peak Mount Rose Area 12/11/2017 - 12:00 Snowpack Observation Forecaster
Becker Ridge Echo Summit Area 12/10/2017 - 12:30 Snowpack Observation Snow coverage at 7400 ft. Snow coverage at 7800 ft. on N aspects. Looking up the ridge toward Becker Peak @ 7900 ft. Forecaster
Castle Pass Donner Summit Area 12/10/2017 - 12:10 Snowpack Observation Educator
Tahoe Mountain School
Mount Price Desolation Wilderness Area (including Emerald Bay) 12/10/2017 - 11:35 Avalanche Observation Public
Relay Peak Mount Rose Area 12/09/2017 - 12:00 Snowpack Observation E face of Relay Peak, 10,200'.  Wind scoured by the recent NE/E winds. NW/W bowls of Relay Peak.  Wind scoured in areas and wind loaded in areas with hard slabs. 2' of cohesive hard slab P to K hard.  F hard facets below.  CTM-12 SC on facet layer. ECTPV.  292 degree W/NW slope, 19 degree slope angle. Forecaster
Elephants Back Carson Pass Area 12/09/2017 - 11:00 Snowpack Observation Public
Granite Chief 12/08/2017 - 14:00 Snowpack Observation E/SE ridge on the approach to Granite Chief. Granite Chief to Needle Ridge. Educator
Alpenglow Expeditions
Castle Peak Donner Summit Area 12/08/2017 - 12:30 Snowpack Observation View of N side of Castle Peak View towards Basin Peak Previous cornince collapse/wind slab that probably failed last Sunday during or just after storm event and partially covered. Forecaster
Red Lake Peak Ridge Carson Pass Area 12/08/2017 - 10:00 Snowpack Observation Thin crust over 5 inches of loose facets which are sitting on pencil hard old snow. Professional Observer