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 button above.
Date and time of observation or avalanche occurrence Location Region Observation Type Photos Snowpack, Avalanche, Weather Videos Snowpit videos (tests, etc) Observation made by
12/26/2019 - 11:00 Silver Peak Cabin Creek, Deep Creek, or Pole Creek Area Snowpack Observation E winds were wrapping around scouring the ridge on to NW/N terrain. New cornice formation building out on ridge. Skin track refill within an hour. Snowpit location with ECTN on small wind slab. Forecaster
03/17/2020 - 12:30 Hidden Peak West Shore Area Snowpack Observation Skier triggered wind slab on a small NE facing test slope near the top of Hidden Peak Developing breakable crusts on east aspects in the early afternoon. Small snow squalls would blow through occasionally. Forecaster
04/25/2020 - 10:30 Donner Peak Donner Summit Area Snowpack Observation Recent loose wet avalanche activity and cornice collapses. Recent cornice fall. Soft edgeable snow at 8:30am on W aspects Deep wet snow on E aspects at 9:30am Forecaster
12/15/2019 - 12:30 Slab Cliffs Mount Rose Area Snowpack Observation Wind scouring and texture on near and above treeline terrain. Wind scouring on shaded NW aspects near treeline. Small cornice kicks did not show any signs of propagation. Forecaster
01/29/2020 - 11:00 Incline Peak/Slab Cliffs Mount Rose Area Snowpack Observation P+ hard wind slab over 4F rimed crystals, SE aspect. Rimed crystals from under wind slab. Looks similar to surface hoar but is not. Wind scouring of NE aspect ridgeline. Signs of minor wind effect below treeline on N aspect. Remains of old Jan 4 PWL in the snowpit at noted lat/long. No signs of current instability here. Forecaster
12/17/2019 - 11:00 Silver Peak Cabin Creek, Deep Creek, or Pole Creek Area Snowpack Observation Hard wind slab at treeline with obvious snow surface texture that we chose to avoid. 10mm surface hoar on a slight NE aspect at ~7,150'. Forecaster
02/28/2020 - 11:15 Incline Lake Peak Mount Rose Area Snowpack Observation Widespread cloud cover today Some softer weaker snow on sheltered untracked N aspects Weak refreeze on a tree covered sun-exposed slope Wind scoured firm surfaces on open areas near and above treeline Artificially loaded PST with about 10 cm of "slab" on top of it to test the current snow surface Results of the artificially loaded PST 40/100 Slab Fracture Forecaster
01/15/2020 - 11:30 Rose Knob Mount Rose Area Snowpack Observation Consistent setup in this area.  4-6'' of recent storm snow on top of Jan 4 rain crust.  Weak faceted snow around this rain crust. Ski cuts on small wind loaded test slopes produced no results. Cornices were reactive, but no signs of wind slab failure on slope. Forecaster
03/25/2020 - 11:00 Andesite Peak Donner Summit Area Avalanche Observation Small D1 wind slab avalanche intentionally triggered. Propagation of wind slab to right flank. Small wind slab failure on small test slope. 8-10'' wind slabs failing on a buried graupel layer. Small loose dry sluffing on slopes >35 degrees. Forecaster
04/11/2020 - 11:00 Relay Peak Mount Rose Area Snowpack Observation ECTX on persistent weak layer at site of skier triggered avalanche on April 8. Recent NE winds have scoured most exposed terrain near and above treeline. Light wind drifting along ridges. A thin, but firm crust softened quickly this morning. Forecaster
03/27/2020 - 12:00 Silver Peak Cabin Creek, Deep Creek, or Pole Creek Area Avalanche Observation Wind slab avalanche that failed on a buried surface hoar layer on Wed. March 25 ECTP 15 on a N facing below treeline slope. The test failed on a layer of buried surface hoar. Forecaster
02/10/2020 - 12:15 Mt. Judah Donner Summit Area Snowpack Observation Variable snow surface conditions throughout area. South facing terrain still firm at 12noon with no signs of softening. Large downed tree from the NE wind event yesterday. Forecaster
01/04/2020 - 12:00 Lincoln Ridge Yuba Pass Area Snowpack Observation Fragile cornice with unreactive 4 inch thick wind slab below. Forecaster
03/12/2020 - 11:30 Powderhouse Peak Luther Pass Area (including Job and Freel) Snowpack Observation Forecaster
01/09/2020 - 11:30 Castle Peak/Andesite Peak Donner Summit Area Avalanche Observation New wind slabs failing on Jan 4 crust. Small D1 wind slab on E aspect Shooting cracks in wind loaded terrain Small loose dry sluffing. Low level clouds with periods of very light snow. Forecaster


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