These observations document past conditions at a small and variable scale. They are not to be confused with an avalanche forecast. They come from a variety of sources. We can only vouch for the quality of those produced by the SAC forecasters and professional observers.
Date and time of observation or avalanche occurrence Location Media Observation made by
01/23/2016 - 11:55
Snowpack Observation 		Andesite Meadows
Donner Summit Area 		Forecaster
12/28/2022 - 11:30
Snowpack Observation 		Andesite Peak
Donner Summit Area 		Small cornice collapse on Andesite Ridge PS 5-10 cm at all elevations Guide
International Alpine Guid
03/06/2019 - 13:00
Avalanche Observation 		Andesite Peak
Donner Summit Area 		Right flank of slide Left flank of slide Public
03/06/2013 - 08:00
Avalanche Observation 		Andesite Peak
Donner Summit Area
Professional Observer
03/13/2023 - 12:15
Avalanche Observation 		Andesite Peak
Donner Summit Area 		Storm slab, intentionally skier triggered, BTL terrain around 7,800' Storm slab, intentionally skier triggered, BTL terrain around 7,800' Storm slab cracking while breaking trail in wind protected BTL terrain. Moving above the skin track so that the storm slab was undercut made it easy to identify the layering. Shooting crack Forecaster
01/15/2017 - 13:00
Snowpack Observation 		Andesite Peak
Donner Summit Area 		Guide
Tahoe Mountain Scho
04/19/2022 - 11:30
Snowpack Observation 		Andesite Peak
Donner Summit Area 		Wind slab failure triggered by a ski kick on an E-ENE facing test slope. Skier triggered wind-slab failure on a wind-loaded test slope. Skier triggered shooting cracks on a wind-loaded test slope. About 6 inches of new snow on top of a thin melt freeze crust with a deep layer of wet snow below it. Minor cracking around my skis in sheltered terrain. Forecaster
01/22/2023 - 08:45
Snowpack Observation 		Andesite Peak
Donner Summit Area 		Drifting snow depositing as a hard slab on W aspect terrain. Thin melt-freeze crust from warming on Saturday. Smooth, supportable hard slab on NW aspect terrain near treeline. Substantial wind scouring on E aspect terrain near treeline. Substantial wind texture on E aspect terrain below treeline. Forecaster
11/25/2020 - 11:00
Snowpack Observation 		Andesite Peak
Donner Summit Area 		Cloud cover along the Sierra Crest with mostly light SW winds below 8000'. Snow available for transport in near treeline terrain. Great opportunity for avalanche rescue practice. Avalanche rescue practice. Forecaster
01/20/2017 - 15:45
Avalanche Observation 		Andesite Peak
Donner Summit Area
D2 Wind slab avalanche triggered by a small cornice piece
Small avalanche triggered by a larger piece of cornice
Cracking in the storm snow on in below treeline terrain
 Forecaster
02/12/2019 - 11:45
Snowpack Observation 		Andesite Peak
Donner Summit Area 		Moderate amounts of blowing snow noted as we approached near treeline terrain. Skin track refill in above treeline terrain. Skier triggered shooting crack 20 ft long and 1 ft deep in wind slab on test slope. Another party's snowboard cut did not produce results on this wind loaded slope. Forecaster
01/26/2021 - 11:00
Snowpack Observation 		Andesite Peak
Donner Summit Area 		Public
12/01/2018 - 11:00
Avalanche Observation 		Andesite Peak
Donner Summit Area 		One of several natural wind slab avalanches on Andesite Peak, E aspect, ~8,100'. Cracking triggered while breaking trail below treeline. Early signs of the instability in the area. The first wind loaded feature we approached at treeline, E aspect,~7,900'. Intentional remote skier triggered avalanche. View from triggering location. 20' shooting crack to where avalanche occurred. Pointing to far flank on the large bump in low visibility. 20' skier triggered shooting crack in near treeline terrain, ENE aspect. Another natural wind slab avalanche, above treeline terrain, ENE aspect, ~8,100'. Still another natural wind slab avalanche, above treeline terrain, ENE aspect, ~8,100'. Wide propagation with the far flank about 2/3rds of the way across the open slope in the background. Easily 200' wide. Forecaster
04/10/2021 - 14:30
Snowpack Observation 		Andesite Peak
Donner Summit Area 		South Side of Castle Peak losing snow quickly Educator
Tahoe Mountain Scho
12/18/2016 - 14:00
Snowpack Observation 		Andesite Peak
Donner Summit Area 		NE wind scouring at 8200' Andesite Peak4'' recent storm snow over firm rain crust. Faceting occuring around recent rain crust.NE wind scouring at 8200' E aspect of peak. Guide
Tahoe Mountain Scho

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