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 button above.
Date and time of observation or avalanche occurrence Location Region Observation Type Photos Snowpack, Avalanche, Weather Videos Snowpit videos (tests, etc) Observation made by
03/15/2020 - 13:30 Donner Ridge Donner Summit Area Snowpack Observation Ski kick triggered crack on a NE facing wind drifted test slope along the ridge @ 7800 ft. A ski kick triggered a small cornice piece that fell onto this slope and released a 8 to 10 inch deep soft wind slab on the test slope below it. NE facing 7800 ft. Poor visibility due to blowing snow and flat light Forecaster
12/22/2019 - 12:00 Rubicon Peak West Shore Area Snowpack Observation Forecaster
04/07/2020 - 11:00 Mt. Judah Donner Summit Area Snowpack Observation Natural loose wet avalanche on north aspect, 7500'. Large built out cornices along ridgelines. Breakable crusts on E aspects with a dusting of snow on top. Forecaster
02/29/2020 - 12:00 Castle Peak Donner Summit Area Snowpack Observation Wet surface snow on top of a thick refrozen melt freeze crust on top of more wet snow on a SE aspect at 8000 ft at 10:40 am Firm refrozen melt-freeze conditions on a S aspect at 8300 ft. @ 11:00 am Corn snow conditions on a SE aspect at 8000 ft at 10:30 am. Raised tracks and firm scoured surfaces on an exposed NE aspect at 8200 ft. Forecaster
04/12/2020 - 11:00 Yuba Pass Yuba Pass Area Snowpack Observation Breakable surface crust from weak refreeze. Surface crust nearly all melted in sunny areas at 9:45 am. Easily triggered roller balls and pinwheels on a NE aspect at about 7,000'. Large pinwheel intentionally triggered from the slope above. March 24 buried surface hoar layer still a concern. March 24 surface hoar crystals under 10x magnification. Forecaster
11/25/2019 - 11:30 Incline Lake Peak Mount Rose Area Snowpack Observation Wind scouring begins in the trees on northerly aspects as slopes get steeper. Near and above treeline terrain was scoured down to dirt and rocks from recent NE wind events. 1-2mm facets exist in below treeline terrain in a very shallow snowpack. 2-5'' snow coverage in below treeline terrain. Forecaster
01/21/2020 - 12:00 Elephants Hump Carson Pass Area Snowpack Observation Ridgetop drifting from strong SW winds. Intentionally triggered rollerballs, NE aspect at ~8,000'. Location of test pit 1. Location of test pit 2. Location of test pit 3. Forecaster
01/13/2020 - 12:00 Andesite Peak Donner Summit Area Snowpack Observation Active wind loading continuing over the higher ridges and peaks. Cracking on new cornice formation. Minor cracking in newly forming wind slabs today. Recent storm snow on top of the Jan 4 rain crust.  NE aspect at 7800' in open treed location. Forecaster
04/01/2020 - 12:00 Carpenter Ridge Independence Lake Area Snowpack Observation Cornice drops onto wind loaded slope with no results. Breakable surface crusts.  Softening occurred on solar aspects. Wet and soft surface snow by 11am on areas with direct sun. Forecaster
04/30/2020 - 10:30 Rubicon Peak West Shore Area Snowpack Observation Small loose wet sluff on a short steep slope above a tree-well at 11 am. Below 7300 ft. very little snow remains. Shin deep wet snow on an E aspect at 9000 ft. at 11 am. Rocks and bare ground melting out on an E aspect at 8500 ft. Some firm uneven snow surfaces near the summit of Rubicon on wind-exposed N aspects at 10:30 am. Forecaster
01/05/2020 - 11:30 Slide Mountain Mount Rose Area Snowpack Observation Soft supportable spring snow on southerly aspects below 8600'. Open areas near treeline terrain with wind scouring. S side of Slide with mostly adequate snow coverage. Thin surface rain crust with buried surface hoar and facets below crust. Forecaster
02/06/2020 - 11:45 Slide Mountain Mount Rose Area Snowpack Observation Signs of a developing loose wet avalanche problem (E aspect, ~9,600'). Snow coverage above 9000' on south aspect. Snow coverage on lower portion down to 8200'.  It goes, or at least it went today! Forecaster
01/19/2020 - 13:00 Slab Cliffs Donner Summit Area Snowpack Observation Forecaster
04/12/2020 - 14:00 Mt. Price Desolation Wilderness Area (including Emerald Bay) Avalanche Observation Forecaster
12/16/2019 - 12:00 Ophir Peak Mount Rose Area Snowpack Observation Forecaster


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