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
04/21/2018 - 12:00 Castle Peak Donner Summit Area Snowpack Observation 3-5'' of wet surface snow on top of a semi supportable m/f crust at 12:30pm. Guide
04/21/2018 - 09:30 Andesite Peak Donner Summit Area Snowpack Observation Poor snow surface refreeze on open E aspect at 7,600'. About 3 inches of weak crust on top of 3 inches of residual storm snow on top of older melt-freeze crust. Residual wet snow in the deeper snowpack. Skier triggered roller balls on mid slope avalanche path on Andesite Peak. NE aspect at 7,900' at 9:15 am. Skier triggered roller balls on the summit of Andesite Peak. NE aspect at 9:45 am. Forecaster
04/20/2018 - 11:30 Castle Peak Donner Summit Area Snowpack Observation Small loose wet activity on E aspects at 10:30am at 8000'. Up to 4-6'' of transitional snow on many NW-N-NE aspects.  Mostly ski supportable but not boot supportable. Minor wind scouring on N aspects from recent NW winds. Guide
04/20/2018 - 11:30 Red Lake Peak Carson Pass Area Avalanche Observation Public
04/20/2018 - 10:30 Rubicon Peak West Shore Area Snowpack Observation Human triggered roller ball showing developing instability. N aspect, below treeline, ~7,900', 10 am. Easily skier triggered loose wet avalanche on test slope. E aspect, at treeline, 9,040', 10:40 am. Forecaster
04/19/2018 - 11:00 Mt. Judah Donner Summit Area Snowpack Observation Mix of sun and snow showers over the Sierra Crest. Breakable melt-freeze crust on N aspects. Supportable melt-freeze crust over recent storm snow on ESE aspect @ 8,200'. Forecaster
04/18/2018 - 10:30 Rubicon Peak West Shore Area Snowpack Observation Increasing cloud cover and the approaching storm. Breakable crust was widespread on E-NE-N aspects at all elevations Graupel layer at the base of the recent snow. Forecaster
04/17/2018 - 12:30 Slab Cliffs Mount Rose Area Snowpack Observation Loose wet sluff triggered by a ski cut on a steep ENE aspect at 9000 ft. Forecaster
04/16/2018 - 12:30 Carson Pass south near Elephant's Back Carson Pass Area Snowpack Observation Minimal results kicking on a below tree line test slope. Pretty sastrugi growing into the wind. Steep below tree line features displayed loose dry slide characteristics in response to skier activity. Small wind slab on a convex roll in near tree line terrain. Professional Observer
04/16/2018 - 11:00 Andesite Peak Donner Summit Area Snowpack Observation Small wind slab triggered by large cornice drop on a ENE facing test slope at 8040 ft. See video. Small 1 to 4 inch slab triggered on an E facing test slope @ 8040 ft. that had just received a short period of sun-exposure The other side of the small slab triggered on the E facing test slope. New snow and some wind-loading filling in the skin track @ 8160 ft. About 30 cm (1 ft) of new snow resting on top of a moist crust on top of wet snow in a meadow at 7500 ft. Forecaster
04/15/2018 - 11:00 Powderhouse Peak Luther Pass Area (including Job and Freel) Snowpack Observation Still adequate snow coverage for travel at lower elevations but dry patches are growing. Firm surface snow conditions around 9000 feet on north facing slopes at 11:30am. Professional Observer
04/15/2018 - 09:30 Andesite Peak Donner Summit Area Snowpack Observation Increasing cloud cover over the Sierra Crest at 9:30 am. One inche of surface wet snow on ESE aspect at ~8,100' at 9:30 am. Forecaster
04/14/2018 - 16:45 Looking at the area below Needle Peak behind Squaw' Shirley Lake Donner Summit Area Avalanche Observation Slide happened between 15:45 and 16:42 based on two photos I took. Public
04/14/2018 - 12:00 Stevens Peak Carson Pass Area Snowpack Observation Small loose wet avalanche intentionally skier triggered at 12pm on NE aspect at 8800' Up to 3-4'' of transitional snow on N-NE aspects. Forecaster
04/13/2018 - 13:15 Maggie's Peak South Desolation Wilderness Area (including Emerald Bay) Snowpack Observation Skier triggered loose wet avalanche, 8,350', ENE aspect, 1:15pm. N and NE aspect terrain above Azure Lake in full sun with April high sun angle. Forecaster