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
01/08/2020 - 12:45 Silver Peak Cabin Creek, Deep Creek, or Pole Creek Area Avalanche Observation
One of 5 intentionally triggered D1 wind slabs in near treeline terrain.
Another of 5 intentionally triggered D1 wind slabs in near treeline terrain.
11/20/2019 - 11:30 Tamarack Peak Mount Rose Area Snowpack Observation Strong NE winds scouring northerly aspects on exposed ridge. Hourglass Bowl scoured down to mostly bare ground and rock. S-SW-W aspects getting wind loaded by strong NE winds right over the ridge of Hourglass Bowl. Minor cracking in fresh wind slabs formed today. Small areas of faceted snow from early season snow in September/October. Forecaster
12/01/2019 - 11:00 Andesite Peak Mount Rose Area Snowpack Observation Small cornice kicks on test slopes did not initiate any avalanches. HS=95cm Some starting zones not filled in yet with rocky terrain. Forecaster
12/05/2019 - 12:00 Indian Valley Ebbetts Pass Area Snowpack Observation Professional Observer
12/09/2019 - 12:00 Castle/Basin Peak Donner Summit Area Avalanche Observation Human triggered avalanche.  200' wide. 12/9 photo The failure layer appears to be buried surface hoar. 12/9 photo SAC Forecaster standing at burial location.  2 main debris paths. 12/10 photo 200' wide, 1-2' deep, failing on a covex rollover. 12/10 photo Mid slope crown. 12/10 photo Looking downslope at the terrain. Debris visible below. 12/10 photo Large shooting cracks out into less steep terrain. 12/10 photo Hole from full burial excavation. 12/10 photo Forecaster
12/14/2019 - 11:45 Hidden Peak West Shore Area Snowpack Observation Dense wind affected new snow near the summit with minimal ski penetration. Poor conditions at 6,600'. Improving conditions at 7,100'. Good coverage at 7,500'. Dec 12 rain crust on summit ridge exposed by wind scouring. Dec 12 rain crust in the snowpit at 9,100'. Forecaster
12/15/2019 - 12:00 Twin Peaks Ridgeline Blackwood Canyon or Ward Canyon Area Avalanche Observation Professional Observer
12/21/2019 - 13:30 Castle Peak pass Donner Summit Area Avalanche Observation Public
12/24/2019 - 12:00 Red Lake Peak Carson Pass Area Avalanche Observation Blowing snow Wind loading Loose Dry Educator
Lake Tahoe Community College - Wilderness Education
12/28/2019 - 12:00 Mt. Judah Donner Summit Area Snowpack Observation Stubborn hard wind slab on a W facing test slope with some blocks of debris near the bottom. Wind affected surface snow on an ENE aspect on Wild Flower ridge. The snow was still soft but minor scouring had occurred to scallop the surface. Forecaster
01/01/2020 - 09:30 Castle Peak Donner Summit Area Snowpack Observation Public
01/06/2020 - 11:45 Rose Knob Mount Rose Area Snowpack Observation Upper Rose Knob with supportable snow conditions above 8000'. At 8000' and below, deeper wet snow existed by 12 noon. Previous small point releases on SW aspects near 8000'. Previous small additional loose wet activity. Jan 4 rain crust.  Variable from strong and up to 2'' thick to thin and breakable.  Facets developing below the crust. Forecaster
01/11/2020 - 12:00 Andesite Peak Donner Summit Area Snowpack Observation Skier triggered shooting crack on an ENE facing wind loaded test slope. 10 to 12 in. deep wind slab on a wind loaded test slope. Signs of wind transport in exposed near and above treeline terrain. Forecaster
01/14/2020 - 12:00 Tamarack - Fireplug Saddle Mount Rose Area Snowpack Observation Soft Wind Slabs Public
01/17/2020 - 13:30 Waterhouse Snowpack Observation Public


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