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
01/13/2019 - 12:00 Upper Cold Stream Canyon Donner Summit Area Snowpack Observation Very large cornice hanging over a steep slope. 1 to 2 cm large surface hoar grains. Old cornice and avalanche debris. What looked like an old avalanche crown on a steep low elevation slope. Forecaster
02/03/2019 - 12:00 Hidden Peak West Shore Area Snowpack Observation Blowing snow with limited visibility at 9200'. Shooting cracks off of skis while skinning up, at 9000' on a NE aspect. At 7600', around 4'' of wet snow on top of a supportable crust. Above 8200', 12'' of new snow. Forecaster
11/29/2018 - 11:30 Castle Peak Donner Summit Area Snowpack Observation High intensity wind loading at ridge top above treeline. High intensity wind loading at ridge top above treeline. Minor skier triggered cracking of newly formed wind slabs. Forecaster
02/04/2019 - 12:00 Mt. Rose Backcountry Mount Rose Area Avalanche Observation Mostly buried avalanche on Tamarack Peak Mostly filled in avalanche crown on Relay Peak Cornice debris from a mostly buried cornice collapse and wind slab avalanche on Tamarack Peak Forecaster
12/14/2018 - 11:00 Deep Creek Cabin Creek, Deep Creek, or Pole Creek Area Snowpack Observation Pit location above avalanche path below. Trim line and runout zone just visible in background. Minor amounts of blowing snow noted along the Sierra Crest between Tinker's Knob and Anderson Peak. Forecaster
02/08/2019 - 13:00 Trimmer Peak Luther Pass Area (including Job and Freel) Snowpack Observation Increasing clouds and wind transport observed along ridges near peak top. Skin track was filling in with light snow transport. Surface hoar was found in isolated areas in protected open below treeline terrain. Minor cracking was observed in wind loaded terrain as small wind slabs were forming. 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
12/11/2018 - 12:00 Carpenter Ridge Independence Lake Area Snowpack Observation Small wind slab at treeline on NE aspect. Unconsolidated snow along the ridgetop, still available for future wind transport. Forecaster
11/28/2018 - 12:00 NW Castle Peak Donner Summit Area Snowpack Observation Light wind loading occurring off of summit ridge with cornice development. Wind loaded pillows showed minor cracking.  Forecaster
02/05/2019 - 01:00 Crag Peak West Shore Area Avalanche Observation Crown line visible mid slope on Crag Peak.  Seen from Jakes Peak View into Desolation Wilderness and Dicks Peak.  Some avalanche activity could be made out in the distance but most was covered up by additional snow. Forecaster
02/18/2019 - 13:30 Lincoln Ridge Yuba Pass Area Snowpack Observation Cornice drop on a test slope that did not trigger any slab instabilities but did cause a sluff. Rain crust exposed by scouring on the ridge. Settlement cone on a tree in below treeline terrain. Deep crack behind a cornice that has pulled away from the ridge. ECTN on a sheltered slope. The rain crust / rain layer has started to refreeze but still had some wet snow at the bottom of the layer. Forecaster
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
12/09/2018 - 12:00 Castle - Basin Peak Area Donner Summit Area Snowpack Observation Wind slab failure on buried surface hoar on a wind-loaded test slope. Shooting cracks triggered by a ski cut on a near treeline wind-loaded test slope. This slab failed on buried surface hoar. Large surface hoar on the snow surface in a sheltered area , Forecaster
01/30/2019 - 12:00 Jakes Peak West Shore Area Snowpack Observation 1 to 2 inches of corn on a supportable surface at 11:15 am on a S aspect. 2 to 3 inches of corn snow on a supportable surface at 12:15 on the same S aspect. Cloud cover moved into the area around 1 pm and you can still see sunlight glinting off of exposed crusts in the distance. Smoke cloud with a flat top showing the height of the morning's inversion. Forecaster
01/14/2019 - 12:00 Johnson Canyon Donner Summit Area Snowpack Observation 10 to 12mm surface hoar in open areas near and below treeline. Forecaster


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