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
12/11/2015 - 11:30 Castle Peak Donner Summit Area Snowpack Observation Forecaster
12/30/2016 - 12:00 Castle Peak Donner Summit Area Snowpack Observation Minor snow transport off peak with limited available snow. 7900' in Round Valley-up to 1cm+ surface hoar. Forecaster
02/24/2016 - 11:00 Castle Peak Donner Summit Area Snowpack Observation Forecaster
12/11/2017 - 13:00 Castle Peak Donner Summit Area 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
01/31/2018 - 13:00 Castle Peak Donner Summit Area Snowpack Observation Large cornices exist along the Castle/Basin Ridgeline.  Forecaster
04/07/2016 - 11:00 Castle Peak Donner Summit Area Snowpack Observation Forecaster
01/02/2018 - 12:00 Castle Peak Donner Summit Area Snowpack Observation Upper elevations on Castle Peak are firm, wind scoured surfaces on NW-N-NE aspects.  Forecaster
11/09/2017 - 12:00 Castle Peak Donner Summit Area Snowpack Observation Cornice sections above test slopes easily collapsed with intentional efforts. No signs of wind slab instability revealed on the test slope below.Supportable snow cover at ~7,900' between the Grub Hut and Castle Pass. Forecaster
01/02/2017 - 10:45 Castle Peak Donner Summit Area Snowpack Observation One of many wind loaded/wind slab test slopes that avalanched with minimal human triggering. Forecaster
11/15/2015 - 14:00 Castle Peak Donner Summit Area Snowpack Observation Forecaster
12/27/2015 - 12:20 Castle Peak Donner Summit Area Snowpack Observation Public
11/28/2017 - 11:45 Castle Peak Donner Summit Area Snowpack Observation Blowing snow near the summit of Castle Peak as observed from vicinity of noted lat/long. Forecaster
04/15/2016 - 11:45 Castle Peak Donner Summit Area Snowpack Observation Forecaster
01/12/2018 - 12:45 Castle Peak Donner Summit Area Snowpack Observation Surface hoar on top of a frozen rain crust in a sheltered meadow at 7600 ft.ECTP failing on the moist facets below a strong slab layer on a NW aspect at 8300 ft.Frozen surface crust on a NW aspect along the ridgeline at 8400 ft.Soft wet snow surface on a SW aspect @ 8200 ft at 1:30 pm. 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

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