Please remember that these observations indicate what was going on in the snowpack at a single point in time and space. They may not represent conditions where you are or where you plan to be. They also come from a variety of sources. SAC cannot vouch for the quality or accuracy of any observations that come from the general public. Some of these may be professional quality observations; some may not. Please use observations listed on this page as part of your information gathering process, but as always don't make decisions based on a single piece of information.

If you are looking for more information on how to understand the information on this page, all of the pit data graphs and stability tests are part of what is presented in a Level II avalanche class that follows the American Avalanche Association (AAA) or American Institute for Avalanche Research and Education (AIARE) curriculum guidelines. All of the coding and abbreviations for data presented follows the publication Snow, Weather, and Avalanches: Observational Guidelines for Avalanche Programs in the United States (SWAG) which is the standard for all professional avalanche programs in the US. An electronic copy is available here. Most of what you are looking for is in Chapter 2 and Appendix F part 1. We use a program called SnowPilot to create the snowpit graphs. It is available as an online tool or as a downloadable program at http://www.snowpilot.org/. This website also has a quick video and user guide on how to use create snowpits. Please send us your observations using the buttons below.

Date and time of observation or avalanche occurrence Location Region Observation Type Photos Videos Observation made by
12/19/2015 - 12:30 Andesite Ridge Donner Summit Area Snowpack Observation Public
04/14/2016 - 10:45 Andesite Ridge Donner Summit Area Snowpack Observation Forecaster
02/07/2017 - 08:30 Andesite Ridge Donner Summit Area Avalanche Observation
Crown from wet slab avalanche triggered by natural cornice collapse.
Cornice and avalanche debris.
Older wet slab avalanches on NE-E aspects. These were widespread in the area.
Forecaster
11/27/2016 - 07:00 Andesite Ridge Donner Summit Area Avalanche Observation Guide
Tahoe Mountain School
03/13/2017 - 13:00 Andesite Ridge Donner Summit Area Snowpack Observation 1pm.  Boot top boot pen and full length ski pole pen on S aspects at 7500'. Guide
Tahoe Mountain School
03/30/2017 - 13:30 Andesite Ridge Donner Summit Area Snowpack Observation Small 2 inch deep wind slab on a wind-loaded test slope at 8000 ft. A dusting of new snow on top of a breakable crust with wet snow down to the handle of the inverted pole at 7800 ft. Forecaster
12/23/2017 - 14:30 Andesite Ridge Donner Summit Area Snowpack Observation Wind loaded area on Andesite RidgeCloud cover and thin coverage on S. side of Castle Peak Educator
Tahoe Mountain School
01/05/2016 - 12:00 Andesite Ridge Donner Summit Area Avalanche Observation
Forecaster
01/27/2017 - 12:00 Andesite Ridge Donner Summit Area Snowpack Observation Wind transport and scouring along Andesite RidgeSkier triggered crack on a wind loaded W facing test slopeNatural cracking on a wind loaded W facing test slope Forecaster
01/16/2017 - 12:50 Andesite Ridge Donner Summit Area Snowpack Observation Guide
Tahoe Mountain School
02/11/2016 - 10:30 Andesite Ridge Donner Summit Area Snowpack Observation , , Educator
Donner Summit Avalanche Seminars
12/17/2017 - 12:07 Andesite Ridge Donner Summit Area Snowpack Observation Surface Conditions mix of sustrugi and melt freeze crusts Educator
Tahoe Mountain School
12/03/2017 - 12:00 Andesite Ridge Donner Summit Area Snowpack Observation CTE Failure 15-20cm down in the snow packShooting Cracks up to 25 feet in length Educator
Tahoe Mountain School
02/19/2017 - 14:00 Andesite Ridge Donner Summit Area Snowpack Observation Guide
Tahoe Mountain School
12/20/2015 - 12:30 Andesite ridge Donner Summit Area Snowpack Observation Public

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