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
01/13/2016 - 11:00 Andesite Peak Donner Summit Area Avalanche Observation
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
12/13/2017 - 11:30 Andesite Peak Donner Summit Area Snowpack Observation Pit location adjacent to and above pit from Dec 6. (Skis/pack in old pit.) Forecaster
12/14/2016 - 11:30 Andesite Peak Donner Summit Area Snowpack Observation Rain runnels existed up to Peak level (8200'). Forecaster
02/03/2016 - 10:00 Andesite Peak Donner Summit Area Snowpack Observation Forecaster
02/12/2017 - 14:00 Andesite Peak Donner Summit Area Snowpack Observation Guide
Tahoe Mountain School
03/03/2018 - 12:30 Andesite Peak Donner Summit Area Snowpack Observation Small wind slab failure. Skin track refillafter 45 min by wind drifted snow on the summit of Andesite Pk. Forecaster
12/04/2016 - 13:00 Andesite Peak Donner Summit Area Snowpack Observation Guide
Tahoe Mountain School
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
03/17/2018 - 12:30 Andesite Peak Donner Summit Area Avalanche Observation The second of two intentionally skier triggered wind slabs in E aspect terrain above treeline. The first of two intentionally skier triggered wind slabs in E aspect terrain above treeline. Two foot crown. 1.75 m (5.75 ft) of storm snow. CTH results with broken failure planes within the storm snow. ECTX in same pit. Signs of storm snow settlement on tree cones at 10am. The second of the two triggered wind slabs. Initial efforts created loose dry. Once the wind slab was triggered from a more prime location, the slab propagated back through the area that had previously failed as loose dry closer to the snow surface. Forecaster
11/10/2017 - 13:00 Andesite Peak Donner Summit Area Snowpack Observation Public
02/02/2017 - 11:00 Andesite Peak Donner Summit Area Avalanche Observation
Storm Slab.  4'' deep, 7900', NE aspect.
Debris from storm slab (D1).
Storm slab, 4'' deep, 7900', NE aspect.
Wind Slab, 4-8'' deep, 8100', E aspect, 38 degree slope.
Forecaster
04/21/2018 - 09:30 Andesite Peak Donner Summit Area Snowpack Observation Poor snow surface refreeze on open E aspect at 7,600'. About 3 inches of weak crust on top of 3 inches of residual storm snow on top of older melt-freeze crust. Residual wet snow in the deeper snowpack. Skier triggered roller balls on mid slope avalanche path on Andesite Peak. NE aspect at 7,900' at 9:15 am. Skier triggered roller balls on the summit of Andesite Peak. NE aspect at 9:45 am. Forecaster
04/07/2017 - 12:00 Andesite Peak Donner Summit Area Snowpack Observation Shooting cracks on wind loaded ridgeline near peak.  8200', E aspect.Wind loading with large built out cornices along upper ridge.ECTN's with no propagation in wind loaded terrain, 8100', E aspect. Forecaster

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