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
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
03/25/2018 - 10:30 Andesite Peak Donner Summit Area Avalanche Observation Natural wind slab below the summit of Andesite, E aspect, ~8,200'. Appeared to have occurred late on March 24. 6 inches of storm snow available for wind transport in above treeline areas. Dark line is our skin track. Minor cracking on wind loaded test slope above treeline. Forecaster
11/23/2016 - 10:30 Andesite Peak Snowpack Observation Public
01/13/2016 - 10:30 Andesite Peak Donner Summit Area Snowpack Observation Forecaster
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
01/07/2016 - 10:50 Andesite Peak Donner Summit Area Avalanche Observation
Guide
Tahoe Mountain School
12/16/2016 - 12:30 Andesite Peak Donner Summit Area Snowpack Observation Small localized cracking in wind loaded terrain.  E aspect 8200'Small cornice kicks did not cause any wind slab failure.  8200', E aspect.ECTN and ECTP in wind loaded E aspect.  8200'.Cracking around skis into non frozen rain crust 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
12/18/2016 - 14:00 Andesite Peak Donner Summit Area Snowpack Observation NE wind scouring at 8200' Andesite Peak4'' recent storm snow over firm rain crust.  Faceting occuring around recent rain crust.NE wind scouring at 8200' E aspect of peak. Guide
Tahoe Mountain School
02/18/2017 - 14:21 Andesite Peak Donner Summit Area Snowpack Observation Public
04/15/2017 - 15:30 Andesite Peak Donner Summit Area Snowpack Observation Intentionally skier triggered loose wet avalanche on test slope entraining about the top 1 foot of the snowpack.Closer up view of same loose wet test slope avalanche.Skier triggered roller ball, ~2 ft diameter.Skier triggered roller ball, ~2.5 ft diameter. Forecaster
01/15/2017 - 13:00 Andesite Peak Donner Summit Area Snowpack Observation Guide
Tahoe Mountain School
12/02/2017 - 12:00 Andesite Peak Donner Summit Area Snowpack Observation Photo 1: Average height of snow near summit of AndesitePhoto 2: South Face of Castle Guide
Alpenglow Expeditions
02/10/2017 - 12:00 Andesite Peak Donner Summit Area Snowpack Observation Cornice kicks on test slopes produced limited loose snow with no signs of slab propagation.2x ECTN's on wind slabs off summit.  8200', E aspect. Forecaster
01/20/2017 - 15:45 Andesite Peak Donner Summit Area Avalanche Observation
D2 Wind slab avalanche triggered by a small cornice piece
Small avalanche triggered by a larger piece of cornice
Cracking in the storm snow on in below treeline terrain
Forecaster

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