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
02/26/2019 - 06:00
Avalanche Observation 		Andesite Peak
Donner Summit Area 		NE aspect below treeline with 2 to 3 ft crown visible. Slope angle ranged from 32 to 44 degrees. Skier's left side of crown and debris. Skier's right side of crown and debris. Crown of 2-3 feet with 8 inches of storm snow on bed surface. ECTX and CTH-Broken results in crown at 11:45am. This is the maximum amount of cracking we observed today in areas of wind slab. Ski cuts such as this in wind loaded terrain above treeline produced no results. Forecaster
03/08/2016 - 10:50
Snowpack Observation 		Andesite Peak
Donner Summit Area 		Educator
Donner Summit Avalanche Semina
01/06/2019 - 12:00
Avalanche Observation 		Andesite Peak
Donner Summit Area 		One of the skier triggered wind slabs near the top of Andesite Peak Small wind slab failure on a test slope. A second ski kick at the spot just after the photo was taken triggered a large whumpf. Skier triggered D1 wind slab avalanche on NE aspect at 8000'. 50' wide x 70' long. Another small D1 skier triggered avalanche in similar terrain. Cracking started at the trailhead 8 inches of new snow acculumated at the trailhead while we were out. My pole is pushed into the level of our skin track when we started the day. Forecaster
12/02/2016 - 12:00
Snowpack Observation 		Andesite Peak
Donner Summit Area 		Forecaster
03/13/2017 - 10:10
Snowpack Observation 		Andesite Peak
Donner Summit Area 		Educator
Donner Summit Avalanche Semina
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
02/24/2018 - 16:15
Snowpack Observation 		Andesite Peak
Donner Summit Area 		Shooting crack on an E facing wind loaded test slope @ 7900 ft. after a few hard stomps The same test slope after a few more stomps. The wind slab slid down the small test slope. Forecaster
02/11/2017 - 13:30
Snowpack Observation 		Andesite Peak
Donner Summit Area 		Near treeline terrain at 7900'. Extensive wind loading and transport.Small test slopes on wind loaded S-SW aspects did not show any cracking. Guide
Tahoe Mountain Scho
03/20/2013 - 09:30
Avalanche Observation 		Andesite Peak
Donner Summit Area
Professional Observer
03/17/2021 - 11:00
Snowpack Observation 		Andesite Peak
Donner Summit Area 		Cloud cover drastically slowing snow surface melt. Breakable melt-freeze crust on southerly aspects and flat terrain. Surface melt-freeze crust formed in the past 24 hours. Minor amounts of surface wet snow formation on a wind protected, below treeline, open E aspect, at about 7,700'. Forecaster
01/15/2017 - 13:00
Snowpack Observation 		Andesite Peak
Donner Summit Area 		Guide
Tahoe Mountain Scho
04/15/2018 - 09:30
Snowpack Observation 		Andesite Peak
Donner Summit Area 		Increasing cloud cover over the Sierra Crest at 9:30 am. One inche of surface wet snow on ESE aspect at ~8,100' at 9:30 am. 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
12/01/2022 - 14:42
Snowpack Observation 		Andesite Peak
Donner Summit Area 		Guide
Alpenglow Expeditio

Pages