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
03/12/2016 - 13:30 Andesite Ridge Donner Summit Area Avalanche Observation
01/21/2016 - 14:30 Tamarack Peak Mount Rose Area Snowpack Observation Forecaster
04/11/2016 - 10:30 Donner Peak Donner Summit Area Snowpack Observation Forecaster
03/16/2018 - 12:00 Andesite Peak Donner Summit Area Avalanche Observation Largest wind slab avalanche triggered by small cornice piece dropped onto the ENE facing slope. A secondary slide released and that crown is 3 to 4 ft. deep. Small wind slab that propagated all the way around an E-ENE-NE facing test slope. Triggered from a low angle slope on the side. Storm slab in below treeline terrain triggered from the lower angle slope I am standing on. Wind slab in near treeline terrain on an ENE facing slope. We cleaned the box on the sign off at the start of our tour and ~3 hours later 6 to 8 inches of snow had accumulated on the box. Forecaster
11/29/2017 - 12:00 Castle Peak Donner Summit Area Snowpack Observation Cornices above the N side of Castle PeakSurface hoar on a N aspect at 8500 ft. Small wind slab on a wind loaded test slope. The slab only measured about 5-10 cm (2-4 in) thick and did not extend downslope very far.ECTN on a wind loaded test slope at 8800 ft. on a NE aspect at the coordinates attached to the observation. Forecaster
02/17/2017 - 15:00 Fireplug Mount Rose Area Snowpack Observation ECTN 20 that broke at the base of the wind slab on a NW aspect, indicating that fractures are unlikely to propagate along this layer. Very small cracking on W aspect along the ridgelines. These small wind-loaded features did crack but the wind slabs remained too small to have consequences. Forecaster
12/13/2016 - 12:00 Tamarack Peak Mount Rose Area Snowpack Observation Snowpit at 9200'.  N-NW aspect.  Facets visible above basal ice.2-3mm facets at 9760'Surface rain crust below 9000' Forecaster
01/04/2018 - 23:30 Chickadee Ridge Mount Rose Area Snowpack Observation Facets below slab remaining dry to moist.Skier triggered roller balls in low angle terrain, indicating possibility of loose wet avalanche potential. Forecaster
02/02/2018 - 12:30 Fireplug Mount Rose Area Snowpack Observation Small roller balls and pinwheels on a SE aspect at 9100 ft. Forecaster
03/09/2017 - 11:00 Incline Lake and Rose Knob Peak Mount Rose Area Snowpack Observation Debris from large ski-cut-triggered pinwheels and roller balls.More pinwheels on a smaller slope at about 3 ft. in diameterDivots and runnels created by the recent warming. Forecaster
03/24/2017 - 11:30 Incline Lake Peak Mount Rose Area Snowpack Observation Snow and wind starting in the morning hours.3-5'' wind slabs formed off of summit ridge on N aspects. Forecaster
12/07/2015 - 10:30 Polaris Point Blackwood Canyon or Ward Canyon Area Snowpack Observation Forecaster
11/14/2016 - 01:30 Tamarack Peak Carson Pass Area Snowpack Observation Forecaster
04/18/2017 - 12:30 Hidden Peak West Shore Area Snowpack Observation Small loose wet avalanches resulting from cornice pieces dropped onto a NE facing wind-loaded slope near 9100 ft. Small loose wet avalanches resulting from cornice pieces dropped onto a NE facing wind-loaded slope near 9100 ft. Loose wet instabilities on a N facing slope at around 7400 ft. Ski cuts triggered small cracking on a wind-loaded test slope near the summit of Hidden Peak. Forecaster
01/02/2016 - 10:15 Carpenter Ridge Independence Lake Area Avalanche Observation


Subscribe to Central Sierra Nevada / Lake Tahoe Snowpack, Weather, and Avalanche Observations for California and Nevada from SAC