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 button above.
Date and time of observation or avalanche occurrence Location Region Observation Type Photos Snowpack, Avalanche, Weather Videos Snowpit videos (tests, etc) Observation made by
01/01/2020 - 14:00 Donner Ridge/Sunrise Bowl Donner Summit Area Snowpack Observation Breakable rain crust on Donner Ridge Forecaster
02/27/2020 - 11:30 Mt. Judah Donner Summit Area Snowpack Observation Early signs of a developing loose wet avalanche problem at 11:30 am on at S aspect at ~7,800'. Superficial refreeze of the top 2 inches of the snowpack with wet snow below in areas under forest canopy. Forecaster
03/18/2020 - 11:00 Martis Peak Avalanche Observation The whole path from crown to debris Looking up at the avalanche crown Avalanche crown at the left side Left flank of the avalanche Right flank of the avalnache Cracks on lower angle terrain adjacent to the right side of the crown. Cracks on a adjacent lower angle slope around a small ridge Looking up from the toe of the debris with a person for scale. Forecaster
02/02/2020 - 11:00 Tahoe Meadows Mount Rose Area Snowpack Observation Incoming storm with cloud deck at 8800'.  Light snow starting late morning. Thin breakable crust on northerly aspects at all elevations. Variable firm conditions on all aspects. Forecaster
12/09/2019 - 12:00 Castle/Basin Peak Donner Summit Area Avalanche Observation Human triggered avalanche.  200' wide. 12/9 photo The failure layer appears to be buried surface hoar. 12/9 photo SAC Forecaster standing at burial location.  2 main debris paths. 12/10 photo 200' wide, 1-2' deep, failing on a covex rollover. 12/10 photo Mid slope crown. 12/10 photo Looking downslope at the terrain. Debris visible below. 12/10 photo Large shooting cracks out into less steep terrain. 12/10 photo Hole from full burial excavation. 12/10 photo Forecaster
12/28/2019 - 12:00 Mt. Judah Donner Summit Area Snowpack Observation Stubborn hard wind slab on a W facing test slope with some blocks of debris near the bottom. Wind affected surface snow on an ENE aspect on Wild Flower ridge. The snow was still soft but minor scouring had occurred to scallop the surface. Forecaster
01/23/2020 - 10:30 Stoney Ridge West Shore Area Snowpack Observation Forecaster
12/14/2019 - 11:45 Hidden Peak West Shore Area Snowpack Observation Dense wind affected new snow near the summit with minimal ski penetration. Poor conditions at 6,600'. Improving conditions at 7,100'. Good coverage at 7,500'. Dec 12 rain crust on summit ridge exposed by wind scouring. Dec 12 rain crust in the snowpit at 9,100'. Forecaster
04/13/2020 - 10:00 Mt. Judah Donner Summit Area Snowpack Observation Debris from recent cornice fall, likely occurred on Apr 10 or 11. Deep almost unsupportable wet snow on ESE aspect at about 8,000' around 11 am. Forecaster
03/11/2020 - 11:45 Ophir Peak Mount Rose Area Snowpack Observation Increasing clouds in the late morning hours. Forecaster
02/14/2020 - 13:00 Johnson Canyon Donner Summit Area Snowpack Observation Snow coverage was patchy on W and SW aspects below 6800 ft. Shallow corn conditions (~2 cm or 1 in of soft wet snow on a supportable frozen base) existed on W and SW aspects as of 1 pm. W and WSW aspects still have decent coverage above 6800 ft. SSW aspects are melting fast. Forecaster
03/18/2020 - 12:00 Incline Lake Peak Mount Rose Area Snowpack Observation Large cornices near the top of Incline Lake Peak Cracking on a small wind-loaded slope near the ridge Snowy weather and limited visibility during the tour. Forecaster
03/30/2020 - 10:00 Silver Peak Cabin Creek, Deep Creek, or Pole Creek Area Snowpack Observation Drifting snow over N ridge of Silver Peak. Wind slab cracking in previously undercut area. Minimal snow still available for transport on S side of E ridge of Silver Peak. Forecaster
12/03/2019 - 12:30 Castle Peak Donner Summit Area Snowpack Observation Good snowcover at 8,000'. Snowpack height 1-1.5m on N aspect. Settlement around trees at ~8,600'. Wet snow with tree dripping and bombing at ~7,900' on W aspect. Wet surface snow, but supportable and over 1m deep at the start of the Castle Rd (~7,300'). Forecaster
02/21/2020 - 12:00 Chickadee Ridge Mount Rose Area Snowpack Observation Coverage on the S side of Slide Mtn Uneven snow surface on a SE aspect at 8900 ft. It was softening by 11 am. Variable conditions including scoured firm snow, soft snow, and breakable crusts on N aspects Shallow corn snow on S-SE aspects between 8000 and 9000 ft by 11:30 am Forecaster


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