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
01/16/2019 - 11:30 Rubicon Peak West Shore Area Snowpack Observation Shooting crack triggered while breaking trail. Connects ski pole to ski pole and beyond for a total of ~20'. Digging out the crack to look at the weak layer of buried surface hoar and density change. Forecaster
04/12/2019 - 12:30 Donner Summit - Black Wall Snowpack Observation The melt/freeze crust started to become unsupportable on S-SE-E aspects below 7000 ft. by 12:30 The melt/freeze crust was still boot supportable as of noon on S-SE-E aspects. 1 to 2 inches of wet corn snow on top of a 6 inch thick melt/freeze crust on an E aspect at 10 am. About 16 inches of wet snow existed below the crust. Glide cracks on an E aspect. Forecaster
01/04/2019 - 11:15 Lincoln Ridge Yuba Pass Area Snowpack Observation NE aspect wind scoured terrain at/just above treeline. Exposed rain crust on upper start zone, wind scoured mid slope, unconsolidated snow at treeline. Established tree well hazard if the forecasted 1-2+ feet of new snow verifies. Forecaster
12/16/2018 - 14:30 Powderhouse Peak Luther Pass Area (including Job and Freel) Snowpack Observation Increasing clouds and some light precipitation over the Sierra Crest in the late afternoon. ECTX when testing the lower layers of the snowpack. Forecaster
01/07/2019 - 08:00 Mt. Judah Donner Summit Area Avalanche Observation Several natural avalanches on Mt. Judah occurring at different times throughout the 1/5-1/7 storm cycle.  Some avalanches ran full path to bottom flats.  8100', E aspect. Different angle of Mt. Judah avalanches.  Some debris mostly covered and some looks to have occurred towards the end of the storm. Multiple natural wind slab avalanches on Wildflower Ridge, 7800', NE aspect. Forecaster
02/25/2019 - 11:00 Peak 9269' West Shore Area Snowpack Observation Intense blowing snow in below treeline areas at 8000'. 1cm layer of 2-3mm graupel on top of the 2/14 rain crust. Right side up snowpack with the thick 2/14 rain crust down 78cm. Forecaster
01/11/2019 - 11:00 North Side Castle Peak Donner Summit Area Avalanche Observation Debris pile. Crown as see from the ridgetop to the east. Crown as see from the ridgetop to the east. Looking E along the crown at the point of the collapsed cornice. Spot where footprints close to the edge triggered the cornice collapse. Forecaster
04/02/2019 - 11:00 Donner Peak Donner Summit Area Avalanche Observation D2 loose wet natural avalanche that ran 400-600'+. D1 loose wet natural avalanche Forecaster
01/31/2019 - 10:15 Johnson Canyon Donner Summit Area Snowpack Observation 2 inches of corn on a supportable melt-freeze layer on a W aspect at 1:15 Crack in the snowpack as a cornice pulls away from the ridge. Forecaster
12/03/2018 - 12:00 Slab Cliffs Mount Rose Area Snowpack Observation Forecaster
04/09/2019 - 12:00 Mt. Judah Donner Summit Area Snowpack Observation Thin melting crust over wet deep wet snow on an E aspect at 10 am. No more crust just deep wet snow by noon on the same E aspect. Ski cut triggered loose wet sluff on a nearby E aspect at noon. Firm scoured rain crust near Wildflower Ridge Variable dust on crust and exposed crust conditions. The weather was a mix of snow squalls and sun. Forecaster
03/23/2019 - 12:00 Castle Peak Donner Summit Area Snowpack Observation 6 inches of new snow overnight on the Castle Rd. Well bonded to crust at old/new interface. Ski cut on this a several other wind loaded test slopes produced no results. Enough drifting snow to refill our up track near Castle Pass. 4f hard sun crust on E slopes of Andesite after a period of thinning cloud cover. Forecaster
12/30/2018 - 11:00 Silver Peak Cabin Creek, Deep Creek, or Pole Creek Area Snowpack Observation Signs of wind scouring on an exposed ridge. Forecaster
04/15/2019 - 11:30 Jakes Peak West Shore Area Snowpack Observation Mostly cloudy skies with some partial sun breaks. 8000', E aspect, at 11:15am.  1-2'' of soft wet snow on top of a 2'' 1f MF crust on top of more wet snow. Forecaster
02/07/2019 - 12:00 Davis Creek Mount Rose Area Snowpack Observation Davis Creek area as seen on Feb 7 with Feb 5 avalanche noted below arrow. Forecaster


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