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 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
02/19/2019 - 13:45 Trimmer Peak Luther Pass Area (including Job and Freel) Snowpack Observation Public
11/23/2018 - 10:30 Grouse Rock Blackwood Canyon or Ward Canyon Area Snowpack Observation Public
12/01/2018 - 07:45 Castle Peak Donner Summit Area Avalanche Observation Public
12/01/2018 - 03:15 N Judah trees Donner Summit Area Snowpack Observation Public
12/09/2018 - 13:15 E of Boreal ski area Donner Summit Area Snowpack Observation Educator
Donner Summit Avalanche Seminars
12/14/2018 - 11:00 Deep Creek Cabin Creek, Deep Creek, or Pole Creek Area Snowpack Observation Pit location above avalanche path below. Trim line and runout zone just visible in background. Minor amounts of blowing snow noted along the Sierra Crest between Tinker's Knob and Anderson Peak. Forecaster
12/17/2018 - 13:00 Castle Peak Donner Summit Area Snowpack Observation Small windslab under 4cm of soft snow cracking The wind affected layer that broke in the previous photo. Soft snow removed on left side to show the slab. ECTN 12 @ the new windslab layer. Public
12/21/2018 - 09:15 Powderhouse Luther Pass Area (including Job and Freel) Snowpack Observation Natural roller ball activity below treeline on Luther Pass. A good number of tree bombs were falling as snow became saturated. Widespread cracking near and above treeline. Very reactive wind slabs on small test slopes. Looking down this small test slope at the bed surface, stauch wall, and debris. Looking across bed surface at crown and flanks. Professional Observer
12/28/2018 - 12:00 Chickadee Ridge Mount Rose Area Snowpack Observation Public
01/05/2019 - 16:30 Becker Ridge Echo Summit Area Snowpack Observation Professional Observer
01/08/2019 - 15:00 Andesite Peak Donner Summit Area Avalanche Observation Public
01/11/2019 - 11:45 Little Alaska, Ward Canyon, Lake Tahoe Blackwood Canyon or Ward Canyon Area Snowpack Observation Location where large, overhanging cornice broke off today. Public
01/15/2019 - 08:00 Jake's Peak West Shore Area Snowpack Observation A view of the pit with distinct layers. Snow fall rates picked up to S1 or S2 as we continued to ascend. Minor surface instabilities/slough (NSF and new snow) were easy to trigger in steeper terrain. Public
01/16/2019 - 01:30 Bottom of Waterhouse Luther Pass Area (including Job and Freel) Snowpack Observation Educator
Alpine Skills International (ASI)
01/21/2019 - 12:00 Tamarack Peak Mount Rose Area Snowpack Observation Intense snow transport on ridges, peak, and even below treeline from strong NW/N winds Small wind loaded test slopes in near treeline terrain did not signs of wind slab propagation Limited cracking on small wind loaded features. Forecaster


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