These observations document past conditions at a small and variable scale. They are not too be confused with an avalanche forecast. They come from a variety of sources. We can only vouch for the quality of those produced by the SAC forecasters and professional observers.
Date and time of observation or avalanche occurrence Location Region Observation Type Photos Snowpack, Avalanche, Weather Videos Snowpit videos (tests, etc) Observation made by
04/04/2021 - 12:00 The Sisters Carson Pass Area Snowpack Observation Firm and textured snow surface as we gained our high point at The Sisters. As we lost elevation, the snow became punchy and unsupportable, with many turns resulting in deep trenches. Not much snow remaining on steep, sunny aspects in this area. A few roller balls were observed initiating from rocks. Several cornices in the area appeared threatening. Professional Observer
04/05/2021 - 11:30 South Side Red Lake Peak Carson Pass Area Snowpack Observation Looking south from Red Lake Snow coverage on the south side of Red Lake Peak Wet surface snow just after midday.  Looking north from Carson Pass Forecaster
04/06/2021 - 11:30 Relay Peak Mount Rose Area Snowpack Observation Strong refreeze of the top 9 inches of the snowpack. Several inches of wet snow and tiny roller balls but still ski supportable at 11:30 am on S aspect near 9,500'. Forecaster
04/06/2021 - 13:22 Round top to Kirkwood Carson Pass Area Snowpack Observation Frozen surfaces on ascent. Trace amounts of snow above 9000' Old firm wind effected snow 3-4" of loose snow @ 9000' on S-facing aspect. Professional Observer
04/07/2021 - 11:15 Castle Peak Donner Summit Area Snowpack Observation Boot-top deep wet snow on S-SE aspects in wind sheltered areas below treeline at 11:20 Runnels on the snowpack indicating water draining through the snowpack Firm surfaces on wind exposed W and SW aspects in above treeline terrain at 11 am. S-SE aspects had 1-2 inches of soft wet snow on them. Snowpack melting out at lower elevations Areas of unsupportable wet snow under the tree canopy 10:30 Forecaster
04/08/2021 - 11:30 Mt. Houghton Mount Rose Area Snowpack Observation Mt. Houghton SE/E aspects Strong refreeze with 6''+ melt freeze crust Looking south to Relay Peak Firm crusts near the top of Mt. Houghton, 10,200'. Forecaster
04/09/2021 - 11:00 Mt. Judah Donner Summit Area Snowpack Observation Multiple loose wet avalanches and cornice fall over the last week Superficial refreeze with punchy conditions in the shade at 10:45am on south aspect This slope was snow covered 1 week ago. Forecaster
04/10/2021 - 09:00 Castle Peak Donner Summit Area Snowpack Observation 9 am, 5 inches of surface refreeze with residual wet snow below. 9:10 am, poor snow surface refreeze under heavy forest canopy. Climber's left is SW aspect with more snow, climber's is more S aspect with substantially less snowcover remaining. Forecaster
04/10/2021 - 10:00 Elephant's Back Carson Pass Area Snowpack Observation Street shoes would have done just fine today, as boot penetration was never more than 1" until our departure at 11am. Lots of texture in the snow surface from previous tracks, wind, and early stage sun cupping. Winnemucca Lake had some refrozen meltwater on the surface. Our sunny descent route still had plenty of snow, but connected options are becoming limited. Creek banks eroding, but still crossable where we needed to. There were even some geese in this meadow! Professional Observer
04/10/2021 - 14:30 Andesite Peak Donner Summit Area Snowpack Observation South Side of Castle Peak losing snow quickly Educator
Tahoe Mountain School
04/11/2021 - 10:45 Twin Peaks Blackwood Canyon or Ward Canyon Area Snowpack Observation NNE aspect terrain at 8,600' with sufficient solar radiation for established melt freeze. Transitional snow on shaded N aspect, thin melt-freeze crust over dry snow. Loose wet debris, likely 1-2 days old where the tree shadows are across the gully. Forecaster
04/11/2021 - 12:00 Castle Peak Donner Summit Area Snowpack Observation Thin snow coverage on S side of Castle Peak 2'' of soft snow on top of a 6'' M/F crust at 8600', S aspect just before noon. Educator
Tahoe Mountain School
04/11/2021 - 22:00 Relay peak, Tamarack Peak Mount Rose Area Snowpack Observation View of Relay Peak. Still adequate coverage along Relay Ridge. Boot-sole penetration in a semi-frozen crust, around 8:45 AM Still some loose, cold unconsolidated snow in isolated shaded areas on north-ish facing aspects. Public
04/12/2021 - 11:00 Mt. Houghton Mount Rose Area Snowpack Observation View south towards Relay Peak 2'' of soft corn snow on top of a supportable 6''+ MF crust Some N aspects have transitioned to M/F conditions Other N aspects above 9000' are still full cold winter snow Forecaster
04/12/2021 - 13:08 Tragedy Springs Carson Pass Area Snowpack Observation 1-2" foot pen on E-SE @ 11:30. Dirty snow, loose debris, and rocks in the common riding routes starting to show. Ski pen within the flats @ 8400' around 1430. 10-12" of supportable crust on a sunny slope. Shovel is at the bottom of crust Soft snow observed near rocks Cumulus clouds built throughout the day but never quite developed into thunder heads. Note the highly textured snow surface Professional Observer


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