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
11/21/2016 - 12:00 Castle Peak Donner Summit Area Snowpack Observation Forecaster
04/04/2017 - 11:45 Castle Peak Donner Summit Area Snowpack Observation Deep holes down to flowing creeks1 to 2 inches of corn snow on top of a supportable melt-freeze crust on a SW aspect at 8200 ft. around 11:45 amAnkle deep wet snow on a SW aspect around 7600 ft. around noonWidespread cloud cover looking south from Castle Peak around 11:40 amSunny skies looking north from Castle Peak around 11:40 am Forecaster
11/27/2016 - 12:00 Castle Peak Donner Summit Area Snowpack Observation Forecaster
01/25/2017 - 13:00 Castle Peak Donner Summit Area Snowpack Observation Public
12/03/2017 - 13:00 Castle Peak Donner Summit Area Snowpack Observation Forecaster
01/15/2018 - 14:30 Castle Peak Donner Summit Area Snowpack Observation Forecaster
12/18/2017 - 11:00 Castle Peak Donner Summit Area Snowpack Observation Exposed firm rain crust on an open slope.Wind affected surfaces on a NW aspectCoverage on the N side of Castle. Forecaster
04/23/2017 - 13:15 Castle Peak Donner Summit Area Snowpack Observation , , , , , Public
02/23/2018 - 11:00 Castle Peak Donner Summit Area Snowpack Observation Cornice on the right (E aspect) and wind pillow on the left (W aspect) due to the shift from SW to NE winds., Wind scoured cornices on E aspect between Castle Pass and Castle Pk., Blowing snow along the Castle Pk - Basin Pk ridgeline. No signs of new wind slab formation. Forecaster
04/01/2016 - 11:30 Castle Peak Donner Summit Area Snowpack Observation Forecaster
12/27/2015 - 12:20 Castle Peak Donner Summit Area Snowpack Observation Public
11/10/2016 - 12:00 Castle Peak Donner Summit Area Snowpack Observation , Forecaster
11/15/2015 - 14:00 Castle Peak Donner Summit Area Snowpack Observation Forecaster
11/14/2017 - 13:00 Castle Peak Donner Summit Area Snowpack Observation Snowpit location. Forecaster
01/18/2017 - 11:00 Castle Peak Donner Summit Area Snowpack Observation Skier triggered wind slab @ 11am.  8300', N/NW aspect, 6-8'' crown line.Cornice formation along ridge at 10:30am.Debris from small wind slab failure. Forecaster

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