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
03/23/2019 - 12:00 Castle Peak Donner Summit Area Snowpack Observation 6 inches of new snow overnight on the Castle Rd. Well bonded to crust at old/new interface. Ski cut on this a several other wind loaded test slopes produced no results. Enough drifting snow to refill our up track near Castle Pass. 4f hard sun crust on E slopes of Andesite after a period of thinning cloud cover. Forecaster
03/23/2019 - 11:45 Incline Lake Peak Mount Rose Area Avalanche Observation Public
03/22/2019 - 11:00 Silver Peak Cabin Creek, Deep Creek, or Pole Creek Area Snowpack Observation Cloud cover over the forecast area limiting snow surface melt. About 1 cm on recent storm snow over crust on N-NE aspects. Forecaster
03/21/2019 - 16:00 Eagle Lake Desolation Wilderness Area (including Emerald Bay) Snowpack Observation Glide Crack in top of underlying granite slab Public
03/21/2019 - 12:15 Martis Valley West Mount Rose Area Snowpack Observation Constant cracking while skinning Trees holding a dusting of snow on their north faces, beginning at 6800ft Ski penetration 3-4in Layers marked are (from top): new/old snow interface, very weak layer, beginning of melt/freeze snow, end of melt/freeze snow Rounds taken from melt/freeze layer, mostly 1mm diameter, but stuck together in 3-5mm balls Break from crude shovel shear test Public
03/21/2019 - 12:00 Tamarack Peak Mount Rose Area Snowpack Observation Very small roller balls on a 20 degree slope. None were observed larger than a billiard ball all day. 15cm of fist hardness storm snow on top of 20cm of 1F snow, under that pencil hardness. ECTN6. New storm snow would fracture at the new/old snow interface, but no propagation occurred. Small cornices at the top of hourglass bowl, NE aspect Public
03/21/2019 - 12:00 Elephants Back Carson Pass Area Snowpack Observation Very small roller balls as daytime warming occurred at noon. Sun patches throughout the day with periods of full sun. Very small cracking in wind loaded terrain. Minor wind scouring along Frog Lake Ridge. Forecaster
03/20/2019 - 16:30 Castle Peak Donner Summit Area Avalanche Observation Wind slab from a hand pit. This slab was 5 inches thick. While it did not break super cleanly, it did break with minimal force. This photo shows the slab rotated up 90 degrees. Public
03/20/2019 - 12:30 Rubicon Peak West Shore Area Snowpack Observation 4 inches of wind affected snow near the summit of Rubicon Small inconsequential wind slab near the summit of Rubicon Upper snowpack at around 8000 ft. on an E aspect on Rubicon Cloudy skies looking N from Rubicon. Forecaster
03/20/2019 - 12:00 Tamarack Peak Mount Rose Area Snowpack Observation New snow became sticky when the sun came out with small roller balls. Up to 6'' wind slabs showed minor cracking in the most wind loaded areas. Thick high cloud cover existed throughout the morning hours. Periods of sun with blue skies started around 1pm. Forecaster
03/19/2019 - 12:30 Slide Mountain Mount Rose Area Snowpack Observation Small loose wet instability on a S facing test slope at 9200 ft at 12:50 pm. Ankle deep wet snow on a S facing slope at 8000 ft. at 1 pm Wind affected snow on a N - NW aspect at around 9400 ft. Breakable crust on a N facing slope at 9000 ft. Forecaster
03/19/2019 - 12:00 Mt. Judah Donner Summit Area Snowpack Observation Signs of creep behind cornices. S aspect test slope at ~8,100' showing the presence of loose wet avalanche problem at noon. 6" thick surface melt-freeze layer with supportable crust separating wet snow from dry snow below. Wet snow surface layer at 7,800' on S aspect barely still ski supportable but with near boot top penetration at 12:30pm. Forecaster
03/19/2019 - 11:00 Donner Summit Donner Summit Area Snowpack Observation Photo of the compression test failure we saw in the artificially loaded tests on a shade N aspect. Public
03/18/2019 - 14:30 Hank's Coulior Mount Rose Area Avalanche Observation Public
03/18/2019 - 11:30 Red Lake Peak Carson Pass Area Snowpack Observation Small loose wet avalanches on gully feature just below 9000' at noon. Cold wind blown snow exists on NW-N aspects in this area at 9600' with no signs of surface melt. Forecaster


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