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
02/24/2019 - 11:00 Mt. Judah Donner Summit Area Avalanche Observation East bowl of Mt. Judah with active wind loading.  Small natural wind slab avalanche in upper middle of photo. Cornice along with wind slab failure from ski kick on small test slope at 7400'.  Wind slab up to 8-12'' deep. Firm rain crust exposed in some areas from wind scouring on ridges. Wind scoured ridge with still some snow available for transport.  Ski pen 0, pole pen 6''. Forecaster
02/12/2019 - 11:45 Andesite Peak Donner Summit Area Snowpack Observation Moderate amounts of blowing snow noted as we approached near treeline terrain. Skin track refill in above treeline terrain. Skier triggered shooting crack 20 ft long and 1 ft deep in wind slab on test slope. Another party's snowboard cut did not produce results on this wind loaded slope. Forecaster
11/24/2018 - 12:00 Castle Peak Donner Summit Area Snowpack Observation Pooling water along the Castle Valley Road from 7200-7800' Rain runnels with wet snow to the ground below 7800' Rain crust up to peak at 9100'. Forecaster
02/26/2019 - 06:00 Andesite Peak Donner Summit Area Avalanche Observation NE aspect below treeline with 2 to 3 ft crown visible. Slope angle ranged from 32 to 44 degrees. Skier's left side of crown and debris. Skier's right side of crown and debris. Crown of 2-3 feet with 8 inches of storm snow on bed surface. ECTX and CTH-Broken results in crown at 11:45am. This is the maximum amount of cracking we observed today in areas of wind slab. Ski cuts such as this in wind loaded terrain above treeline produced no results. Forecaster
12/18/2018 - 13:00 Mt. Judah Donner Summit Area Avalanche Observation These wind slab avalanches along Mt. Judah were thought to have occurred mid morning. Shooting cracks in wind loaded terrain on small test slopes at lower elevation. Skier triggered reactive windslabs along Wildflower Ridge. Multiple natural wind slab avalanches along the East Face of Mt. Judah.  All D1 in size. Wind slab avalanches along Mt. Judah were up to 1-2' deep, but did not extend very far downslope. Forecaster
02/16/2019 - 12:00 Rubicon Peak West Shore Area Snowpack Observation Strong SW winds with intense snow transport provided blizzard conditions near the summit. Skin track refill was quick in below treeline terrain. Forecaster
03/02/2019 - 11:15 Jakes Peak West Shore Area Avalanche Observation First avalanche triggered at ~8,700' by intentional ski cut. Moving below 7,800' these avalanches could be triggered by ski cuts on just about any convexity about 34 degrees and steeper. At around 7000', this storm slab/loose wet hybrid triggered by ski cut. Avalanche debris into trees below. Forecaster
04/06/2019 - 10:00 Andesite Peak Donner Summit Area Snowpack Observation About 4 inches of storm snow on top of weak crust and F hard wet snow at 7,300'. Minor cracking of wind slab. 35 cm of wind slab on top of weak crust and F hard wet snow. E aspect at about 8,100' in terrain with above treeline characteristics. Repeatable ECTP-12 down 25 cm within 35 cm of wind slab on E aspect at 8,100'. Foggy conditions above about 7,800'. Forecaster
01/22/2019 - 11:00 Silver Peak Cabin Creek, Deep Creek, or Pole Creek Area Snowpack Observation Digging 2m deep test pit. Surface hoar still well preserved buried 1m down, but unreactive. NE winds scoured ridgetop and upper portion of N aspect start zones down to rain crust. Settlement of most recent storm snow. Forecaster
04/08/2019 - 23:00 Mt Judah Donner Summit Area Avalanche Observation Cornice collapses that triggered loose wet avalanches and a slab failure The other side of the slab Debris at the bottom of the slope form both loose wet and the slab avalanche Another cornice failure near the true summit of Judah. Large chunks of debris at the bottom of this slope. Forecaster
02/19/2019 - 13:00 Deep Creek Cabin Creek, Deep Creek, or Pole Creek Area Snowpack Observation Very small loose dry on NE aspect, 46 degree slope angle, below treeline terrain. Pockets of upright surface hoar on shaded northerly aspects. Skinning through this S aspect wind slab produced no cracking. Minor wind scouring and blowing snow on the summit of Deep Creek Peak. Skin track refill after about 5 min on top of Deep Creek Peak. Wind scouring down to exposed rain crust near the ridgetop. Forecaster
12/08/2018 - 10:45 Mt. Judah Donner Summit Area Snowpack Observation Surface hoar still present on the summit ridge of Judah indicating that the winds did not get strong enough to destroy it last night. Ski tracks on the windward side of Judah indicating that soft snow is still available for transport if the winds increase. Forecaster
02/23/2019 - 12:00 Carpenter Ridge Independence Lake Area Snowpack Observation Minimal amount of snow transport along exposed ridges up to noon.  SW winds did increase at our departure. Along ridges above 8000', up to 12'' of light unconsolidated snow exists for wind transport. Forecaster
12/12/2018 - 12:00 Elephant's Hump Carson Pass Area Snowpack Observation Newly formed pencil hard wind slabs at treeline. Widespread evidence of wind scouring. Elevated tracks on Elephants Back. Forecaster
02/10/2019 - 02:00 Andesite Peak Donner Summit Area Avalanche Observation Forecaster


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