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 Snowpack, Avalanche, Weather Videos Snowpit videos (tests, etc) Observation made by
03/13/2017 - 10:10 Andesite Peak Donner Summit Area Snowpack Observation Educator
Donner Summit Avalanche Seminars
02/03/2016 - 10:00 Andesite Peak Donner Summit Area Snowpack Observation Forecaster
03/16/2018 - 12:00 Andesite Peak Donner Summit Area Avalanche Observation Largest wind slab avalanche triggered by small cornice piece dropped onto the ENE facing slope. A secondary slide released and that crown is 3 to 4 ft. deep. Small wind slab that propagated all the way around an E-ENE-NE facing test slope. Triggered from a low angle slope on the side. Storm slab in below treeline terrain triggered from the lower angle slope I am standing on. Wind slab in near treeline terrain on an ENE facing slope. We cleaned the box on the sign off at the start of our tour and ~3 hours later 6 to 8 inches of snow had accumulated on the box. Forecaster
02/11/2017 - 13:30 Andesite Peak Donner Summit Area Snowpack Observation 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 School
12/21/2017 - 11:00 Andesite Peak Donner Summit Area Snowpack Observation Wind transport of snow at treeline.The maximum extent of cracking seen today in new wind slabs on W-NW aspects. Small 1.5m crack off tip of right ski.Cracking of undercut wind slab on NE aspect at treeline. Forecaster
02/05/2017 - 12:00 Andesite Peak Donner Summit Area Snowpack Observation Guide
Tahoe Mountain School
01/03/2016 - 13:00 Andesite Peak Donner Summit Area Avalanche Observation Guide
Tahoe Mountain School
03/01/2018 - 11:15 Andesite Peak Donner Summit Area Avalanche Observation Small natural storm slab. Small storm slab triggered from below. Wind slab failure on a test slope caused by the natural collapse of a cornice. 1 to 2 foot deep wind slabs failing on the old/new interface on a near treeline wind loaded slope. Triggered from lower angle terrain above the slope. Wind slabs avalanche triggered from the ridge. The avalanche also caused the lower angle slope next to it to shatter but the snow did not slide downhill on the lower angle slope. Shooting crack from lower angle terrain that then becomes a wind slab avalanche in the nearby steeper terrain. Forecaster
03/18/2018 - 12:45 Andesite Peak Donner Summit Area Snowpack Observation RB4 near Andesite Peak Public
03/22/2018 - 11:00 Andesite Peak Donner Summit Area Snowpack Observation Shooting crack on an E - NE facing wind-loaded slope at 8100 ft. Rain runnels at 7500'. Large cornice drops did not cause wind slab failure.  Heavy, wet, deep snow existed at 8200' on the top of Andesite. Forecaster
02/24/2018 - 16:15 Andesite Peak Donner Summit Area Snowpack Observation 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
12/26/2016 - 10:10 Andesite Peak Donner Summit Area Snowpack Observation Forecaster
01/19/2016 - 12:30 Andesite Peak Donner Summit Area Avalanche Observation
Forecaster
12/14/2016 - 11:30 Andesite Peak Donner Summit Area Snowpack Observation Rain runnels existed up to Peak level (8200'). Forecaster
03/03/2018 - 12:30 Andesite Peak Donner Summit Area Avalanche Observation Forecaster

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