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. This program is available as a free download at A video on how to download and use this program is available here. Please send us your observations using the buttons below.

Location Region Observation Type Date and time of observation or avalanche occurrence Avalanche observation video Avalanche photos Snowpit videos (tests, etc) Snowpack photos Snowpit or crown profile photo or graph Observation made by
Silver Peak Cabin Creek, Deep Creek, or Pole Creek Area Snowpack Observation 03/13/2017 - 11:00 Runnels creating less than smooth snow surfaces on ESE aspects (photo left), transitioning to smooth on NE aspects (photo right). Decent supportability in open areas at 9:45am. Cracking of weak melt freeze crust on nil aspect under forest canopy. Poor supportability of surface melt-freeze on N aspect at 6,700' at 9:30am. Forecaster
Andesite Peak Donner Summit Area Snowpack Observation 03/13/2017 - 10:10 Educator
Donner Summit Avalanche Seminars
Slide Mountain Mount Rose Area Snowpack Observation 03/12/2017 - 11:00 Ski and boot supportable snow on solar aspects at 11:30am. Rough snow texture from previous wind and avalanche debris. Forecaster
Donner Ridge Donner Summit Area Snowpack Observation 03/12/2017 - 10:05 Educator
Donner Summit Avalanche Seminars
Rose Knob Mount Rose Area Snowpack Observation 03/11/2017 - 11:30 Small skier triggered loose wet activity. Below 8500' on E/SE aspects, roller ball activity. At 8000' and below, fully unsupportable snow conditions. Forecaster
South Side Castle Peak Donner Summit Area Snowpack Observation 03/10/2017 - 12:00 Consistent boot pen around 1' deep throughout the day. Snow surface runnels from previous melt. Forecaster
Negro Canyon Donner Summit Area Snowpack Observation 03/10/2017 - 12:00 Shin deep wet snow on an east aspect at 7200 ft. Skier-triggered pinwheels up to 2 ft in diameter Forecaster
Carson Pass/West shoulder of Red Lake Pk Carson Pass Area Snowpack Observation 03/09/2017 - 11:15 Rough wind sculpted snow surfaces on S aspect terrain above treeline. Minor amounts of skier triggered rollerballs at 9,600' on SE aspect at 11:15am. Minor amounts ov skier triggered roller balls at 8,900' on SE aspect gully wall at 11:30am. Forecaster
Incline Lake and Rose Knob Peak Mount Rose Area Snowpack Observation 03/09/2017 - 11:00 Debris from large ski-cut-triggered pinwheels and roller balls. More pinwheels on a smaller slope at about 3 ft. in diameter Divots and runnels created by the recent warming. Forecaster
Rubicon Peak West Shore Area Snowpack Observation 03/08/2017 - 11:30 Signs of significant settlement of recent storm snow. Skier triggered roller ball at 8,000' on NNE aspect at 11:30am. Natural roller balls on Crag Peak, E aspect, 9,000'. Site of testpit to examine wind slab. Forecaster
Trimmer Peak Luther Pass Area (including Job and Freel) Snowpack Observation 03/08/2017 - 11:30 Skier triggered roller balls and pinwheels at 10 am on an E aspect. Runnels in the snow surface caused by warming and melting. Forecaster
Tram Ridge, Shirley Canyon Cabin Creek, Deep Creek, or Pole Creek Area Snowpack Observation 03/07/2017 - 14:45 Glide crack in Shirley Canyon Guide
Alpenglow Expeditions
lncline Lake Peak Mount Rose Area Snowpack Observation 03/07/2017 - 10:00 Cornices and blowing snow near the summit of Incline Lake Peak. Limited wind slab cracking isolated to undercut areas. Note the skin track undercut. Forecaster
Hidden Peak West Shore Area Snowpack Observation 03/06/2017 - 12:00 Strong to gale force W winds along the summit ridge. Settlement cracks around trees. Skin track refilling within 20 minutes from wind transport. Forecaster
Powderhouse Peak trees Luther Pass Area (including Job and Freel) Snowpack Observation 03/05/2017 - 14:00 Quick snow pit in an opening in below treeline terrain showed soft new snow (fist hard) transition to harder old snow (4 finger to 1 finger). Multiple graupel events today. In the afternoon wind seemed to shift and begin to gust from the NW. This changed the wind transport in this area and created some wind slab in different locations. Small test slope that failed under a ski kick. Limited cracking in front of a ski. Professional Observer


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