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
12/21/2018 - 11:00 Andesite Peak Donner Summit Area Snowpack Observation Wind loaded test slopes showing unreactive slabs. Minor cracking on old/new snow interface while breaking trail. Skier triggered rollerballs after about 2 hrs of very light rain. Forecaster
12/24/2018 - 11:30 Tamarack Peak Mount Rose Area Snowpack Observation Stormy conditions at Tamarack. Skier triggered crack on a small wind loaded test slope. New wind slab on top of older hard wind slab on top of old weak surface snow. 3 inches of snow on the hood of the truck after we returned from the tour. Forecaster
12/07/2018 - 12:00 West Grouse Blackwood Canyon or Ward Canyon Area Snowpack Observation SE aspect below Grouse Rock. 10cm artificial slab created PST 20/100 end on 12/4 SH layer. New surface hoar of 5 to 10 cm seen in West Grouse area. Forecaster
01/28/2019 - 10:30 Stevens Peak Carson Pass Area Snowpack Observation Cloudy skies kept the snow surfaces firm and frozen. Mostly supportable but sometimes breakable sun crusts existed on E aspects. Firm uneven surfaces including exposed rain crusts existed on E-NE aspects. Small pinwheels and rollerballs triggered by a ski cut on an ENE facing slope around 8200 ft. Forecaster
12/29/2018 - 11:45 Upper Cold Stream Cabin Creek, Deep Creek, or Pole Creek Area Snowpack Observation Photo 1: Looking to the west at NE-E aspect near and above treeline terrain along the Sierra Crest, wind scoured snow surfaces and icy crusts were obvious. Forecaster
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
01/16/2019 - 11:30 Rubicon Peak West Shore Area Snowpack Observation Shooting crack triggered while breaking trail. Connects ski pole to ski pole and beyond for a total of ~20'. Digging out the crack to look at the weak layer of buried surface hoar and density change. Forecaster
11/29/2018 - 10:15 Andesite Peak Donner Summit Area Avalanche Observation Forecaster
12/19/2018 - 11:30 Ellis Peak Blackwood Canyon or Ward Canyon Area Avalanche Observation Intentionally triggered wind slab avalanche, D1. Another photo of same avalanche. 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
12/26/2018 - 12:15 Deep Creek Cabin Creek, Deep Creek, or Pole Creek Area Snowpack Observation No signs of wind effect in open areas below treeline, ~7,900 N aspect'. Minimal signs of wind effect from NE winds on ridgetop at ~8,000'. F hard surface snow with micro-sastrugi. Some exposed rain crust just visible reflecting on the cornice top in upper Pole Creek. 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
12/09/2018 - 12:00 East Ridge Tamarack Peak Mount Rose Area Snowpack Observation Surface hoar failing on an artificially loaded PST. Crusts on windward slopes preventing wind transport of snow with moderate SW winds. Windward SE-S-SW aspects have limited snow in this area. 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
01/02/2019 - 12:00 Above Tom's Valley Independence Lake Area Snowpack Observation Exposed, snomo ski breakable rain crust on ridgetop at ~8,100'. Old fracture failing down to the 12/22 rain crust. Faceted snow at this layer interface still shows problematic failure in snowpit tests. Forecaster


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