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
04/12/2018 - 18:00 North Bowl Castle Peak Donner Summit Area Snowpack Observation West winds transporting snow More west wind transport 4-5" of cold snow still existed on N aspect at 18:30 Public
04/12/2018 - 11:00 Andesite and Castle Peak Donner Summit Area Snowpack Observation Skier triggered shooting crack on a wind loaded E facing test slope Small ski triggered wind slab failure on an E facing test slope Increasing clouds across the Sierra Crest around noon NW winds scouring the ridge on Castle Peak at 11:15 am Forecaster
04/12/2018 - 01:15 Mt. Judah Donner Summit Area Snowpack Observation Public
04/11/2018 - 12:00 Chickadee Ridge Mount Rose Area Snowpack Observation 1 to 3 cm of corn snow on top of a supportable melt-freeze crust at 11:30 am Widespread cloud cover rolling in across the Sierra Crest ahead of tonight's storm Forecaster
04/11/2018 - 03:30 Mr Rose trail just past waterfall Mount Rose Area Avalanche Observation Public
04/10/2018 - 12:30 Mt. Judah Donner Summit Area Snowpack Observation Almost knee deep wet snow on an E aspect at 8000 ft. at 12:15 pm. Rain clouds and rain looking east from Mt. Judah Cracks along Wildflower Ridge as the cornice pulls away from the ridge. Forecaster
04/09/2018 - 08:30 Andesite Peak Donner Summit Area Snowpack Observation Open areas between 7,200' and 8,200' held a refreeze of the top 4 to 6 inches of the snow surface at 8:00 am. Snow surface in melt phase on E aspect at 7,540' at 8:30 am. Forecaster
04/08/2018 - 13:00 Pyramid Peak Desolation Wilderness Area (including Emerald Bay) Snowpack Observation Glide cracks on an E facing granite slab at 8400 ft. 2-4 cm of corn snow on a sunny E aspect at 9000 ft at 1 pm. Large cornice collapses on a NE aspect at 8800 ft. It looks like these occurred during the rain storm. Public
04/08/2018 - 12:00 Carpenter Ridge Independence Lake Area Snowpack Observation Deep slab.  Looked fairly recent but I never got a better view. Wet slide that appeared to have released today.  N bowl of Castle. Rain melt / freeze ice crust Skin penetration around noon on S aspect ~8,000' Public
04/08/2018 - 11:30 Rubicon Peak West Shore Area Snowpack Observation Snow surface refreeze of the top 10 inches of snow on flat terrain at ~7,600' at 10 am. Feet of residual wet snow below the surface refreeze. Surface wet snow 2-3 inches deep at 11:30 am on E aspect at ~8,900' Forecaster
04/07/2018 - 14:00 Tamarack Peak Mount Rose Area Snowpack Observation Breakable refreezing crust with deep wet snow below. Light snow above 10000 ft. on Mt. Rose Rime at 9700 ft on Tamarack Peak. Forecaster
04/06/2018 - 10:45 Andesite Ridge Donner Summit Area Snowpack Observation Knee deep wet snow on an ENE aspect at 7560 ft. Small skier triggered pinwheels on a NE facing test slope. Forecaster
04/05/2018 - 11:30 Johnson Canyon Donner Summit Area Snowpack Observation Spotty snow coverage on low elevation  (below 7400 ft) S and SW aspects. Boot top deep wet snow on an E aspect at 7100 ft. at 11 am. The snow was still barely ski supportable at this time. Forecaster
04/05/2018 - 11:00 Red Lake Peak Carson Pass Area Snowpack Observation Boot pen of only 5 cms on SE aspect at 9000 feet at 1100. Firm frozen snow extended down approximately 25 cms. Softer moist snow below that. Professional Observer
04/04/2018 - 12:00 Mt. Houghton Mount Rose Area Snowpack Observation 12:15pm on E aspect at 9400', 4-6'' boot pen. Forecaster