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
01/04/2018 - 13:00 Mt. Judah Donner Summit Area Snowpack Observation ECTP in an area where the loose weak snow had a small slab on top of it prior to last night's storm.Small loose wet roller balls on a N facing slope at 8000 ft. Forecaster
04/09/2016 - 11:00 Becker Ridge Echo Summit Area Snowpack Observation Forecaster
03/17/2018 - 10:00 Slab Cliffs Mount Rose Area Avalanche Observation Natural storm slab avalanche Additional photo taken and added to this observation on March 19. Forecaster
12/05/2017 - 12:00 Castle Peak and Basin Peak Donner Summit Area Snowpack Observation Scoured surfaces on a N aspect near 8800 ft. on Basin PeakSofter unconsolidated snow on a below treeline N aspect sheltered from the NE winds @ 8200 ft. above Devils Oven Lake.  Forecaster
04/15/2016 - 11:45 Castle Peak Donner Summit Area Snowpack Observation 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
01/08/2016 - 11:00 Andesite Ridge Donner Summit Area Snowpack Observation Forecaster
01/09/2018 - 12:00 Elephants Hump Carson Pass Area Snowpack Observation Natural cracking down into facet layer.More natural cracking down into facet layer.Still more natural cracking down into facet layer. Forecaster
03/02/2017 - 11:00 Rose Knob Mount Rose Area Snowpack Observation Wet loose avalanche skier triggered into gully terrain trap.  E aspect, 7650', 11:56am.Bed surface of loose wet.Looking up at Rose Knob.  Previous wet loose avalanches in gullies. Forecaster
02/03/2018 - 13:30 Underwood Bowl Bear Valley Area Snowpack Observation 2 to 5 cm (1 to 2 in) of corn snow on a S aspect at 3:00 pm.Patchy snow cover on SE-S-SW aspects in the area. Recent cornice collapses and good snow cover on NE aspects.Snow cover on N aspects and lack of snow cover on S aspects in the distance Forecaster
02/19/2016 - 12:30 Castle Peak Donner Summit Area Snowpack Observation Forecaster
03/04/2018 - 11:15 Negro Canyon Donner Summit Area Avalanche Observation Looking up at the crown of the deep slab, left flank. Debris in the trees from the deep slab. Shooting cracks connecting to lower angle terrain. Climber's right end of crown with debris. Avalanche debris Crack in partially excavated pit immeadiately after weak layer collapsed. Photo taken from triggering snowpit location. These cracks ran 500' over to steeper terrain where it remotely triggered this avalanche beyond the view of this photo.  Shooting cracks continued and went a total of 1000' away from this spot into lower angle terrain on the other side of the avalanche. Digging out one of the cracks-see attached snowprofile.  Crack was 153cm deep down to the facet layer. Forecaster
11/15/2015 - 14:00 Castle Peak Donner Summit Area Snowpack Observation Forecaster
11/08/2017 - 11:15 Lincoln Ridge Yuba Pass Area Snowpack Observation Snowpit location with 50cm snow depth, some previous wind loading.Snowcover of about 14 inches at about 7,350'FS Rd 12 at 6,900'. Rd plowed for logging operations. Forecaster
03/20/2018 - 12:00 Proletariat Mount Rose Area Snowpack Observation Looking at the crown. My finger is pointing to the weak layer and the crust is visible where I shoveled out part of the crown. Runnels on an ESE aspect at 9200 ft. Forecaster


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