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
12/04/2018 - 12:00 Silver Peak Cabin Creek, Deep Creek, or Pole Creek Area Snowpack Observation 10-15mm surface hoar in open areas near and below treeline This type of open below treeline terrain has even distribution of large surface hoar across slope. Forecaster
12/06/2018 - 12:00 Castle Peak Donner Summit Area Snowpack Observation 8-10mm surface hoar in Round Valley at 7900'. Rimmed surface snow above 8000', up to 10mm in size. Forecaster
01/07/2019 - 08:00 Mt. Judah Donner Summit Area Avalanche Observation Several natural avalanches on Mt. Judah occurring at different times throughout the 1/5-1/7 storm cycle.  Some avalanches ran full path to bottom flats.  8100', E aspect. Different angle of Mt. Judah avalanches.  Some debris mostly covered and some looks to have occurred towards the end of the storm. Multiple natural wind slab avalanches on Wildflower Ridge, 7800', NE aspect. Forecaster
02/21/2019 - 12:00 Peak 9,269' West Shore Area Snowpack Observation Minor wind slab cracking as we first encountered wind loaded areas. Old cornice/wind pillow scoured back by NE winds on top of N-S oriented ridgetop. 1.5 cm thick sun crust on W aspect at ~9,200'. Crust under ~ 5 inches of recent new snow. Forecaster
01/11/2019 - 11:00 North Side Castle Peak Donner Summit Area Avalanche Observation Debris pile. Crown as see from the ridgetop to the east. Crown as see from the ridgetop to the east. Looking E along the crown at the point of the collapsed cornice. Spot where footprints close to the edge triggered the cornice collapse. Forecaster
01/31/2019 - 10:15 Johnson Canyon Donner Summit Area Snowpack Observation 2 inches of corn on a supportable melt-freeze layer on a W aspect at 1:15 Crack in the snowpack as a cornice pulls away from the ridge. Forecaster
03/27/2019 - 14:00 Powderhouse Peak Luther Pass Area (including Job and Freel) Snowpack Observation Blowing snow along the summit ridge of Powderhouse. Shooting crack on a wind-loaded test slope on @ 9100 ft. on Powderhouse Smal ski cut triggered wind slab on a test slope on Powderhouse Peak. A lull in the storm over Luther Pass between 1 pm and 3 pm today. Forecaster
11/26/2018 - 12:00 Tamarack Peak Mount Rose Area Snowpack Observation True north aspects have the most snow with other aspects showing numerous rocks and bare patches. Looking down the Hourglass from the top of Tamarack Peak. Looking across at Relay Peak. Top of the Proletariat looking down. Forecaster
03/12/2019 - 12:00 Mt. Judah Donner Summit Area Snowpack Observation ECTP 17 on a small wind-loaded test slope. ECTP 19 on a small wind-loaded test slope. Small skier triggered cracking in a newly formed surface wind slab. Variable sun crust on a westerly aspect. Wind-affected snow surfaces. Blowing snow along the summit ridgeline of Mt. Judah Firm icy surface on a wind scoured W aspect. Large cornices overhanging Wildflower Ridge. I decided to go back and around them on the uphill side and stayed very far from the edge of the ridge when I did. Weather moving in from the West to the East. Forecaster
03/31/2019 - 11:00 Castle Peak Donner Summit Area Snowpack Observation Good snow coverage on south slopes on Castle Peak Thin breakable melt freeze crusts with colder unconsolidated snow below. Forecaster
02/07/2019 - 12:00 Davis Creek Mount Rose Area Snowpack Observation Davis Creek area as seen on Feb 7 with Feb 5 avalanche noted below arrow. Forecaster
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
03/17/2019 - 11:00 Upper Ginny Lake drainage. Mount Rose Area Snowpack Observation Thin melt freeze crust over dry snow on flat terrain at 8,350'. Thin melt-freeze crust over dry snow on SE aspect at 9,550'. Same thin melt-freeze crust over dry snow on SE aspect at 9,550'. Shallow wet snow over dry snow on SE aspect at 9,600'. Dry snow previously unaffected by melt on NNW-N-NNE aspects above 8,500'. Forecaster
04/07/2019 - 12:00 Stevens Peak Carson Pass Area Snowpack Observation Mostly sunny skies, warm temps, with thin high cloud cover and strong SW winds. ECTN on wind loaded test slope at 8900', NE aspect.  Roller ball activity along with some small loose wet avalanches. Weak wet snow that failed with a ski turn on lower angle terrain. Forecaster
02/19/2019 - 13:30 Donner Summit Donner Summit Area Snowpack Observation Skier triggered shooting crack on a low angle W aspect Skier cracking on a low angle slope wind-loaded by NE winds and previously undercut by the skin track. Variable wind scoured surfaces with exposed rain crust in some areas. Large surface hoar that was laying flat on many sheltered N-NE-E aspects. Forecaster


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