On this #GivingTuesday, help us develop K-8 materials/activities, enable our scientists to travel to schools to engage with students, and increase our presence at events where we can meet and interact with community. 👉 give.berkeley.edu/fund/FH5846000 Every donation makes a difference!

Happy first day of meteorological winter! We haven't seen a ton of #snow yet but we have had rain, so we're in relatively good shape. With that said, we're hoping to see snow in the forecast sooner than later so we can really start building our seasonal snowpack! #CAwz #CAwater

Interested in getting more information on recent happenings on the lab? Check out our most recent email newsletter that went out today! tinyurl.com/bm3wb95p In it: how the water year has started, the quest for more (and easily accessed) data, and we get a new employee!

11/21/25 8:45am Update: Another 1.2" (3 cm) of #snow fell in the last day, which brings our storm total to 3.9" (10 cm) and our 7-day total to 12.4" (31.5 cm). We are now at 89% of median snowfall and 167% of median precipitation (rain & snow) to-date. #CAwx #CAwater

11/20/25 8:50am Update: We have 2.8" (7 cm) of new #snow with light to moderate snowfall rates continuing this morning. Our 7-day total to 11.6" (29.5 cm). Snow will continue through this evening and is expected to be the last for at least the next 7-10 days. #CAwx #CAwater

11/19/2025: Just a friendly reminder that early season doesn't correlate to the entire season. This is the snowfall that we had on this date in 2023 (0.8") and we still ended with above average snowfall. Early season is highly variable. In other words, it isn't anywhere close to time to panic yet.

11/17/25 9:30am Update: Light to moderate snow in the last 24 hours has resulted in #snow accumulation of 5.1" (13 cm). We're expecting another 3-4" throughout today and tonight. Another storm is on the horizon and is expected to come through around Thurs. #CAwx #CAwater

Applications for this year's CSSL Snow Science School occurring January 14-16, 2026 are now open! We encourage undergrad/grad students and career professionals to apply. Applications close November 15th, 2025, so don’t wait! Get more details here: csslsnowschool.com

10/26/25 9:25am Update: We have 2" (5 cm) of #snow this morning. More precipitation expected today but warm temps means that it will be rain rather than snow. This looks like the only precip for the foreseeable future but early season moisture is always good! #CAwx #CAwater

Applications for this year's CSSL Snow Science School occurring January 14-16, 2026 are now open! Applications close November 15th, 2025, so don’t wait! Get more details here: csslsnowschool.com Apply to attend here: forms.gle/e8uNu6KZi9vH...

Have an interest in weather/water and enjoy tinkering? We're launching the hydrometPi program for students, researchers, or hobbyists that want to build instruments using Raspberry Pi technology! Tutorials and community resources are available on our website. www.hydrometPi.org

How did this year's first #snow date compare to what we've seen in the past? Check out our calendar of first snowfall occurrences below for the details 👇 We're right in that early to mid-October hotspot of activity. #CAwx #CAwater

10/15/25 9:20am Update: It's official! Our first measurable snowfall happened. We had 7.3" (18.5 cm) of #snow accumulation at our measurement this morning. It looks like we're done with snow for at least the next 10 days but we'll be watching the forecast excitedly. #CAwx #CAwater

10/13/25 9:30am Update: Not enough #snow for a measurement this morning because we only measure accumulation greater than 0.5 cm (0.2"). Something tells us we'll have enough within the next 24 hours though... #CAwx #CAwater

10/11/2025 9:15am Update: Models continue to shift as we move closer to our forecasted #snow for the early half of this week. Currently, model guidance suggests 12-16" of accumulation at our lab Mon-Weds and we'll update as we get closer and outlooks change. #CAwx #CAwater

👀 Is it happening? It might be happening. We'll be keeping an eye on the model runs but early next week is looking pretty good... ❄️❄️❄️ #Snow #CAwx

10/2/25 10:25am No snow yet but plenty of rain over the last 24 hours, which is a great start to the 2026 water year that began yesterday. These early rain storms help prime our soil and keep it moist meaning less water from our snow has to do that job later. #CAwx #CAwater

How many lightning strikes have we had around Donner Summit and the Lake Tahoe Basin since Saturday? 1500 - each with its own strength and location characteristics involving drought, fuel loads, and recent meteorological conditions. 1/2

We are looking for a company vehicle with 4x4 or AWD that we can use to get to our field sites. We don't have the biggest budget, so we're working on alternatives to buying new. The vehicle doesn't need to be a newer model or even in great running condition. 1/2 Bad AI pic for attention

The Snow Lab is hiring! We're hiring a Research Scientist to evaluate snowpack mass and energy balance response to precipitation enhancement using the Weather Research and Forecasting Hydrological (WRF-Hydro) and iSnobal models. Details here 👉 www.linkedin.com/jobs/view/42...

6/21/25 1:45pm Update: Ah yes, summertime. Long hours of sunlight, days at the lake, and... SNOW?! Yes, snow. Currently at the lab we have a mix of #snow and #graupel coming down. Nothing says summer serenity like a blanket of white! #CAwx #Weather

Looking for something to do on your Saturday? Come visit us at Legacy Day at Donner Memorial State Park! We'd love to chat with you and load you up with stickers!

The @techreview just released an article that discusses our project to create a system of sensors to measure California's snowpack temperature. Similar work from our partners @DRIScience and @USDA_NRCS is also discussed. Check it out here tinyurl.com/5ahyhtkw

5/13/25 9:45am Update: A fresh blanket of white covers the lab study site after we received 5.9" (15 cm) of late spring #snow in the last day. Other than some flurries today, there's no snow in the forecast, so this could be our last snowfall of the season. #CAwx #CAwater

5/12/25 3:30pm Update: It's not over yet! We've been getting snow all day and it has led to some wonderful spring conditions ❄️❄️❄️

Yesterday we held our final winter and snowpack briefing of the season that corresponded to the final snow survey in #California. Overall, another great season with statewide snowpack reaching average, which makes three years in a row. Check it out here: youtu.be/D6DYrCA7X2Q?...

4/27/25 9:40am Update: Another 4.3" (11 cm) of #snow over the last day brings our season total to 362.99" (922 cm), ~3" (7 cm) over our median annual snowfall of 360" (915 cm). We had 100% of April 1 median for SWE and are now above average for accumulation too! 1/2 #CAwx #CAwater

#Snow started shortly after midnight and we have accumulated 4.5" (11.5 cm) so far with light to moderate rates. We expect more snow through tomorrow with the heaviest rates being overnight tonight and another 5-10" at the lab. #CAwx #CAwater

Mwah hahahaha! You thought it was spring but the weather has other plans! ❄️❄️❄️ We are expecting some late-season snow this weekend (April 26 & 27, 2025) above 6000 feet, most of which will fall Saturday night into Sunday morning. We're currently expecting 6-12" at the lab. #CAwx #CAwater

We're exciting to be participating in the Tahoe Truckee Earth Day Festival this Saturday April 26, 2025 at the Palisade's Tahoe Village! Come out to chat with us about all things snow, our research, and educational programs. Or, just stop by to grab yourself a CSSL sticker!

There are over 250 snow survey sites in California where crews take manual measurements with hollow tubes, known as Federal Samplers, once a month from Feb to May! This video is from late May when we did the Onion Creek in the American River Basin April 1 measurement.

4/8/25 8am Update: Today we're at 115% of median snow water equivalent to-date, largely due to last week's storms. Higher than average temperatures take over today and will continue through Friday, which should substantially increase melt. Ablation season is here! #CAwx #CAwater

DRI’s Anne Heggli working with the @cssl.bsky.social, testing a new method for measuring #snowpack temperature. Thank you, Anne, for sharing pictures of your #fieldwork. Learn more about Anne's work: bit.ly/hegglirainonsnow #ScienceThatMattersNow

Today we've hit 99% of our April 1 average snowpack statewide and 100% of average for this date. That last storm really helped out! Three years at or above average is exceedingly rare in California with the last occurrence being in the late 1990s. Time to celebrate! #CAwater #snow

4/2/25 9:30am Storm Update: 24 hour ❄️: 13.2" (33.5 cm) 2-day snow ❄️: 31.1" (79 cm) Storm total (6-day) ❄️: 43.9" (111.5 cm) Some light #snow showers are possible today and tomorrow but accumulations are only expected to be 0-2" (0-5 cm). #CAwx #CAwater

4/1/25 10:15am Update: This morning in Barbie Land we had 17.9" (45.5 cm) of #snow from the last day, which brings our storm total to 25.4" (64.5 cm) so far. We have now had 341" (866 cm) since the start of the water year on October 1st. More on the way today! #CAwx #CAwater

After a lot of consideration and debate, we have chosen to rebrand due to the high amount of rain that we've received. We will no longer be the Central Sierra Snow Lab but, instead, will be the Basic Atmospheric Research on Basin Inflow Efficiencies (BARBIE) project.

3/31/2025 10am Update: Cold and windy conditions this morning with 7.5" (19 cm) of #snow in the last day and 9.6" (24.5 cm) in the last 2 days. We're expecting 2-4 feet of snow through tomorrow night, which should bring us close to hitting average on April 1! #CAwx #CAwater

5/30/25 09:20am Update: We had 2.2" (5.5cm) of #snow in the last day and moderate to heavy bands of snow are now moving through. Our interval board, used to measure snowfall over a set period of time, is ready to catch plenty of new snow over the next few days. #CAwx #CAwater

🚨 3/30/25 8:55am 🚨 CSSL Web Server Update: Our website is down as UC Berkeley campus IT does critical mechanical and electrical system upgrades. Services will be restored at 10:30pm today.

🚨 3/30/25 8:30am 🚨 We are aware of an issue with our web server and have been investigating. It looks like this may be a larger problem than just our machine and will likely take some time to solve. We'll keep you updated as things progress.

3/29/25 9:45am Update We've had 3.1" (8 cm) of #snow in the last 2 days with 1" (2.5 cm) over the last 24 hours. Tomorrow morning starts a stormy period that should last 4-5 days and is currently expected to bring us 3-4 feet of snow. The season isn't over yet! #CAwx #CAwater

We're expecting a wet start to April with some big time #snow! There's a fair bit of agreement between the American and European ensembles that show us getting up to 60" of snow in the next 10 days. Plot: Experimental snow ensembles from our friends at the University of Utah #CAwx #CAwater

We began a new program with our friends at Donner Memorial State Park this winter. Snow Science Snowshoe Tours were led by lab staff to teach about the importance of snow and how we measure it. The tours were held on February and March 8th and were a hit with 76 people participating!

We've come a long way since the end of January and have gotten back on track. Statewide, the snowpack is now at 95% of its April 1st average, typically the maximum measurement of the season. #Snow #CAwx #CAwater

POV: You're a rock at the bottom of a snow pit seeing the sky for the first time since Nov 12, 2024! We recently hosted students learning about snow at the Headwaters Science Institute. They took the opportunity to talk to our researcher who was making snow pit measurements & observe how it's done.

5/20/2025 10:30am Update: We had 2.2" (5.5cm) of #snow at our measurement this morning. After some light snow showers tomorrow, things will be dry and warm over the next week. We may see the return of precip around April 1 but it's too early to tell for sure. #CAwx #CAwater

The #snow received over the last week has helped bring the statewide snowpack up from 77% to 90% of the April 1 average. However, dry conditions expected to take over later this week and last 7-10 days are likely to prevent us from attaining an average snowpack this year. 1/2 #cawx #CAwater

It is DUMPING out there right now! #snow #CAwx #CAwater

3/17/25 10:45am Update: A snowy morning on the hike into the lab! We had 10.8" (27.5 cm) of #snow this morning and we are now at 54.7" (139 cm) of snowfall over the last week. We're expecting another 5-10" today and have a smaller storm in the forecast for Weds. #CAwx #CAwater