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 http://www.snowpilot.org/. 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
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
01/28/2019 - 12:00 Castle Peak Donner Summit Area Snowpack Observation Looking south down the Sierra Crest.  High level cloud cover preventing widespread snow surface softening Forecaster
01/13/2019 - 15:30 Donner Peak Donner Summit Area Snowpack Observation Educator
Tahoe Mountain School
02/17/2019 - 13:00 Donner Ridge Donner Summit Area Snowpack Observation Skin track, ski pen 10-15cm, ski pole pen 110cm Wind scouring on ridge by Donner Rim trail Public
01/06/2019 - 12:00 Andesite Peak Donner Summit Area Avalanche Observation One of the skier triggered wind slabs near the top of Andesite Peak Small wind slab failure on a test slope. A second ski kick at the spot just after the photo was taken triggered a large whumpf. Skier triggered D1 wind slab avalanche on NE aspect at 8000'.  50' wide x 70' long. Another small D1 skier triggered avalanche in similar terrain. Cracking started at the trailhead 8 inches of new snow acculumated at the trailhead while we were out. My pole is pushed into the level of our skin track when we started the day. Forecaster
12/15/2018 - 14:15 Johnson Canyon Donner Summit Area Snowpack Observation Educator
Tahoe Mountain School
01/20/2019 - 02:30 ASI windlip Donner Summit Area Snowpack Observation Public
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
01/08/2019 - 11:45 Mt. Judah Donner Summit Area Snowpack Observation Signs of up to 6 inches of storm snow settlement in this area. Multi-height ECTN results within the recent storm snow. Large cracks behind cornices from previous natural cornice failures. Forecaster
01/23/2019 - 13:30 Castle Peak Donner Summit Area Avalanche Observation Small loose wet avalanches on south side castle peak Guide
Tahoe Mountain School
12/25/2018 - 15:00 Castle Peak Donner Summit Area Snowpack Observation ECTP 12 on the summit pitch ascending Castle Peak The slab above the pit cracked quite easily. Another quick pit. ECTP 18 farther up in the NW trees of castle peak. 200 vertical feet below the highest trees on that slope skiers right side. Public
12/08/2018 - 11:30 Castle Peak Donner Summit Area Snowpack Observation Extended column test with no failure, Snow pack was 125cm Surface hoar was seen almost everywhere, except for the most sunny areas. Public
02/07/2019 - 14:00 Mt. Judah Donner Summit Area Snowpack Observation Surface hoar varied from 3 to 10mm in size on multiple aspects and elevations. Wind textured snow on the top 50' of Mt. Judah from recent NW-NE winds. Guide
Tahoe Mountain School
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
12/14/2018 - 10:30 Anderson Ridge Donner Summit Area Snowpack Observation High winds but minimal local ridge top transport wind scoured and side loading below the ridge thin and non-reactive wind loading at 10:30a Public

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