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
11/30/2018 - 15:30 Relay Peak Mount Rose Area Snowpack Observation Public
12/01/2018 - 03:15 N Judah trees Donner Summit Area Snowpack Observation Public
12/01/2018 - 07:45 Castle Peak Donner Summit Area Avalanche Observation Public
12/01/2018 - 10:30 Rubicon Peak West Shore Area Avalanche Observation Mostly filled in crown line from a small skier triggered wind slab avalanche about 2 hours before we got there. NE aspect, 39 degree slope, 9100 ft. The crown goes from where I am taking the photo to where my partner is standing. Skier triggered shooting cracks resulting from a storm slab instability on an undercut slope. Skier triggered shooting cracks on a wind-loaded test slope. Lots of obstacles below 7500 ft. Forecaster
12/01/2018 - 11:00 Andesite Peak Donner Summit Area Avalanche Observation One of several natural wind slab avalanches on Andesite Peak, E aspect, ~8,100'. Cracking triggered while breaking trail below treeline. Early signs of the instability in the area. The first wind loaded feature we approached at treeline, E aspect,~7,900'. Intentional remote skier triggered avalanche. View from triggering location. 20' shooting crack to where avalanche occurred. Pointing to far flank on the large bump in low visibility. 20' skier triggered shooting crack in near treeline terrain, ENE aspect. Another natural wind slab avalanche, above treeline terrain, ENE aspect, ~8,100'. Still another natural wind slab avalanche, above treeline terrain, ENE aspect, ~8,100'. Wide propagation with the far flank about 2/3rds of the way across the open slope in the background. Easily 200' wide. Forecaster
12/01/2018 - 12:15 Gareth Feldstein Donner Summit Area Snowpack Observation Wind loading - small cornice 125cm weak top layer roughly 35cm Checking the crust @ 55cm - 30cm Crust @ 55cm Joe - extended column test (Low angle probably prevented negative test results) Wind loading along the ridge-line Lots of wind on the ridge-line Public
12/01/2018 - 12:30 Tamarack peak East aspact at 9800' Mount Rose Area Snowpack Observation Public
12/01/2018 - 14:15 Johnston Canyon Donner Summit Area Snowpack Observation Educator
Tahoe Mountain School
12/02/2018 - 10:00 Broken Glass Mount Rose Area Snowpack Observation Public
12/02/2018 - 10:45 Red Lake Peak - Above Crater Lake Carson Pass Area Avalanche Observation Just before the avalanche was triggered. The skier that triggered it just did a ski cut and then a few more turns with no reaction other than loose sluff. The avalanche would be triggered on the next 1 or 2 turns. The skier that triggered the avalanche took this photo of the loose dry sluff just before the avalanche was triggered. Avalanche debris field. The path dog legs out of sight to the left. Looking back at the upper path of the avalanche. You can ski where the skier went over the buried rocks but was able to ski to safety. The upper crown is 12-14" and lower crown 24-30". Overview of avalanche crown. The first ski cut is visible as well as where the skier stopped after releasing the loose sluff. 24-30" avalanche crown Upper bowl of Red Lake peak is visible with previous ski tracks. The lower part of the avalanche path is obscured by a small ridge line with trees. Public
12/02/2018 - 13:00 Elephants Hump Carson Pass Area Snowpack Observation 2mm surface hoar found throughout area Loose dry sluffing on a steep test slope Wind slab avalanche with debris covered up by additional snow Forecaster
12/03/2018 - 12:00 Slab Cliffs Mount Rose Area Snowpack Observation Forecaster
12/03/2018 - 12:00 Jakes Peak West Shore Area Snowpack Observation Public
12/03/2018 - 12:00 Red Lake Peak Carson Pass Area Snowpack Observation Surface Hoar growing on flat terrain near base of Red Lake Peak. Previous skier triggered slide in sun in middle of photo. Natural slide on left of photo and skier triggered slide on far right. Cracking in front of ski tip. Professional Observer
12/03/2018 - 12:30 Mt. Judah Donner Summit Area Snowpack Observation 10 - 15 mm surface hoar was widespread in the Mt. Judah area. IT did start to melt some on slopes with direct sun-exposure later in the day. Cornice pieces and loose dry surface hoar sluffs on Wild Flower Ridge. Cloud cover rolling into the area in the afternoon. Forecaster


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