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
01/20/2019 - 11:30 Carson Pass Carson Pass Area Snowpack Observation Scoured surfaces on the windward aspects. A mix of new snow on crusts and exposed crusts on leeward slopes. Forecaster
04/05/2019 - 12:00 Mt. Tallac Desolation Wilderness Area (including Emerald Bay) Snowpack Observation Minimal snow surface refreeze at trailhead at 10am (6,520'). Signs of small (D1) loose wet avalanches from past couple of days on E aspect. Signs of accumulating snowfall on crust at 7,800'. Signs of wind slab up to 6 inches deep upon nearing summit ridge in near treeline terrain. Wind slab on summit ridge a the top of Corkscrew avalanche path. 10 inch wind slab of upside down snow (4F+ to F hard) on top of P+ hard crust. 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
12/07/2018 - 12:30 Tamarack Peak Mount Rose Area Snowpack Observation Very large surface hoar was widespread in the Tamarack Peak area. More surface hoar on in an open area on Tamarack Peak Early season conditions still exist especially at the lower elevations. 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
03/07/2019 - 12:00 Mt. Judah Donner Summit Area Snowpack Observation ECTP on a lower density layer of storm snow on an open near treeline aspect at 8060 ft. Wind affected slope on the windward side of a ridge. Settlement cracks around a tree. A very deep tree well. Small cornice dropped on a small wind-loaded test slope with no additional results. Forecaster
01/26/2019 - 11:00 Incline Lake Peak Mount Rose Area Snowpack Observation Recent NE wind events have scoured near and above treeline terrain.  Northerly below treeline terrain like this provided wet and sticky surface snow by noon today below 8600'. On southerly aspects, 3-4'' of wet snow existed above a supportable snow surface. 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
02/01/2019 - 12:00 Tamarack Peak Mount Rose Area Snowpack Observation 4-6mm surface hoar near trailhead in open below treeline terrain at 8700'. 6-8mm surface hoar near Tamarack Peak on E-NE aspects, 9900'. More surface hoar Small avalanche terrain feature, 30-32 degrees, N aspect, with surface hoar present. Forecaster
02/10/2019 - 12:30 Andesite Ridge Donner Summit Area Snowpack Observation Active wind-loading on Donner Summit Small skier triggered cornice failure causing a loose snow sluff on a test slope. Skin track refilled by wind loading. ECTN on the flank of a natural avalanche that occurred last night. Forecaster
02/05/2019 - 12:00 Jakes Peak West Shore Area Snowpack Observation About an inch of settlement crack around trees. 15 cm wind slab at treeline. Ski pen thigh deep. Wind pillow above NE aspect terrain at the summit. Ski cut in wind pillow near summit with no wind slab failure. Convective cell snowing out over Lake Tahoe. Forecaster
11/29/2018 - 11:30 Castle Peak Donner Summit Area Snowpack Observation High intensity wind loading at ridge top above treeline. High intensity wind loading at ridge top above treeline. Minor skier triggered cracking of newly formed wind slabs. 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
03/20/2019 - 12:30 Rubicon Peak West Shore Area Snowpack Observation 4 inches of wind affected snow near the summit of Rubicon Small inconsequential wind slab near the summit of Rubicon Upper snowpack at around 8000 ft. on an E aspect on Rubicon Cloudy skies looking N from Rubicon. Forecaster
01/23/2019 - 11:30 Castle Peak Donner Summit Area Snowpack Observation Wind scoured N aspect terrain. Looking S along Andesite Ridge. Significant wind scouring across the ridgetop. Eroded cornices above SE aspect terrain. Wind scoured N aspect terrain at treeline. Significant settlement of recent storm snow on E side of Andesite. Forecaster


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