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 Videos Observation made by
02/19/2016 - 13:51 Andesite Ridge Donner Summit Area Avalanche Observation
04/07/2016 - 11:00 Castle Peak Donner Summit Area Snowpack Observation Forecaster
01/02/2018 - 12:00 Castle Peak Donner Summit Area Snowpack Observation Upper elevations on Castle Peak are firm, wind scoured surfaces on NW-N-NE aspects.  Forecaster
03/25/2017 - 12:00 Mt. Tallac Desolation Wilderness Area (including Emerald Bay) Snowpack Observation Rapid warming at 9am with full sun.  Loose wet activity occurring on E aspects.Previous wind slab activity from yesterday.  NE aspect, 9000'. Skier triggered loose wet activity, E aspect, 8400', at 11am.Skier triggered loose wet activity on NE aspect, 7500', at 11:15am. Forecaster
01/24/2018 - 23:30 Lake of the Woods. Independence Lake Area Avalanche Observation
Digging into the crown to look at the faceted failure layer.
Subtle line of mostly filled in crown visible ~ 10 ft down slope of person in photo.
Looking down the avalanche path.
12/26/2015 - 14:30 Incline Lake Peak Mount Rose Area Snowpack Observation Forecaster
12/16/2016 - 13:00 Tamarack Peak Mount Rose Area Snowpack Observation PST that failed while isolating the column on the facet layer 160 below the surfaceECTP 25 on a softer snow layer below yesterdays rain crust.Small 4-6 inch wind slab on a NE facing wind loaded test slope. Forecaster
01/22/2017 - 11:20 Negro Canyon Donner Summit Area Avalanche Observation
Witnessed remote trigger wind slab avalanche/test slope failure from ridgetop (SE aspect, 6,880')..
Small natural wind slab avalanche futher up ridge from remote trigger test slope failure (ESE aspect, 7,000').
Signs of recent natural cornice collapse and subtle evidence of a mostly refilled crown line (NE aspect, 7,240')
Rapid storm snow settlement at 6,500.
12/06/2015 - 12:00 East Ridge Tamarack Peak Mount Rose Area Snowpack Observation Forecaster
02/05/2018 - 12:30 Red Lake Peak Carson Pass Area Snowpack Observation Previous point release loose wet avalanche activity at 9000' on E aspect.Small roller balls on test slope.  E aspect at 11:45am. Forecaster
02/05/2016 - 11:00 Mt. Judah Donner Summit Area Snowpack Observation Forecaster
03/28/2016 - 12:00 Tamarack Peak Mount Rose Area Snowpack Observation Forecaster
01/27/2017 - 12:00 Andesite Ridge Donner Summit Area Snowpack Observation Wind transport and scouring along Andesite RidgeSkier triggered crack on a wind loaded W facing test slopeNatural cracking on a wind loaded W facing test slope Forecaster
03/10/2017 - 12:00 South Side Castle Peak Donner Summit Area Snowpack Observation Consistent boot pen around 1' deep throughout the day.Snow surface runnels from previous melt. Forecaster
03/08/2016 - 12:00 Jakes Peak West Shore Area Snowpack Observation Forecaster


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