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
01/23/2020 - 13:00 Waterhouse Peak Luther Pass Area (including Job and Freel) Snowpack Observation Small (1-2mm) surface hoar observed near 7800', NE aspect, 10:00am Large (7-9mm) surface hoar observed near 9380', NE aspect, 2:00pm Educator
Lake Tahoe Community College - Wilderness Education
12/28/2019 - 13:15 Mayflower Ridge Donner Summit Area Snowpack Observation Small windslab on test slope Crown on test slope Wind scouring along ridgelines Another image of widespread wind affect in the Donner Peak area CT19 down 20cm on old (rounding) near surface facets buried during last storm cycle Educator
Tahoe Mountain School
12/20/2019 - 03:15 Wild flower Ridge Donner Summit Area Snowpack Observation Educator
Alpine Skills International (ASI)
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
01/17/2020 - 14:00 Munchkins Area Blackwood Canyon or Ward Canyon Area Snowpack Observation Ski kick triggered shooting cracks on ENE facing wind-loaded slope. Skier triggered shooting cracks on N facing wind loaded slope. Skier triggered shooting cracks on a NW facing slope. Forecaster
11/20/2019 - 11:30 Tamarack Peak Mount Rose Area Snowpack Observation Strong NE winds scouring northerly aspects on exposed ridge. Hourglass Bowl scoured down to mostly bare ground and rock. S-SW-W aspects getting wind loaded by strong NE winds right over the ridge of Hourglass Bowl. Minor cracking in fresh wind slabs formed today. Small areas of faceted snow from early season snow in September/October. Forecaster
01/28/2020 - 11:00 Hidden Peak West Shore Area Snowpack Observation Wind loading along the upper ridges of Hidden Peak Drifting snow near treeline. Traversing the ridgetop and ski cutting numerous test slopes produced no unstable results. Skin track refill in about 20 min. Forecaster
01/01/2020 - 14:00 Donner Ridge/Sunrise Bowl Donner Summit Area Snowpack Observation Breakable rain crust on Donner Ridge Forecaster
12/01/2019 - 11:00 Andesite Peak Mount Rose Area Snowpack Observation Small cornice kicks on test slopes did not initiate any avalanches. HS=95cm Some starting zones not filled in yet with rocky terrain. Forecaster
01/23/2020 - 10:30 Stoney Ridge West Shore Area Snowpack Observation 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
01/03/2020 - 11:00 Castle Peak Donner Summit Area Snowpack Observation Snow surface melting occurred on southerly aspects despite this mid to high level cloud shield during the morning hours. A half to one inch of surface wet snow over supportable wind pack at 11am, S aspect at about 8,200'. Once the rain and melt/freeze crust had melted away, ski and foot pen increased into the dry snow below. Wind protected E aspect at about 7,900'. Once the rain and melt/freeze crust had melted away, ski and foot pen increased into the dry snow below. Wind protected E aspect at about 7,900'. 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
12/13/2019 - 12:00 Incline Lake Peak Mount Rose Area Snowpack Observation Cracking in a new 6 inch think wind slab at midday. More wind slab cracking at midday. Forecaster


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