SACRAMENTO – Snowpack in the Sierra Nevada is currently much lower than what is considered average for this time of year, according to the California Department of Water Resources’ (DWR) first snow survey of the season.
DWR staff conducted the survey on Jan. 2 at Phillips Station — a site located roughly 90 miles east of Sacramento off U.S. Highway 50 — and recorded 7.5 inches of snow depth with 3 inches of a snow water equivalent, which is the measurement of how much water is available from snow. Compared to what is normally recorded at Phillips Station in January, the measured snowpack depth is at just 30% of the average.
“While we are glad the recent storms brought a small boost to the snowpack, the dry fall and below average conditions today shows how fast water conditions can change,” Sean de Guzman, the DWR’s snow surveys and water supply forecasting unit manager, said in a Jan. 2 press release. “It’s still far too early to say what kind of water year we will have, and it will be important for Californians to pay attention to their forecasts and conserve water, rain or shine.”
At a media briefing following the survey, State Climatologist Michael Anderson and Andrew Schwartz, the lead scientist and manager of the UC Berkeley Central Sierra Snow Lab, explained that while the survey results show the winter season is off to a dry start, it is still difficult to predict what the rest of the state’s water year will look like.
After historic flooding last spring, discussions of what residents can expect for 2024 have been circulating, especially since the National Oceanic and Atmospheric Administration (NOAA) first reported an El Niño advisory for North America continuing through March.
Typically, El Nino conditions observed across the Pacific Ocean can result in warmer and wetter than average weather in parts of North America, including California; however, Anderson said that El Nino conditions do not consistently correlate to wet years in the state.
“Last time we had an El Nino winter was in the winter of 2019, and that year we saw some coastal flooding, as well as one of the five largest snowpacks to that date,” Anderson said. “Over the 21st century, we’ve had seven El Nino events, and if we look at the distribution of them, we really span the gamut.”
Anderson said that of those seven El Nino events, California has had two dry years, two wet years and three average years.
“El Nino by itself drives a lot of the variability of our winter weather, (but) it is not the only piece of the puzzle,” Anderson said. “We have a lot of subseasonal climate influences that are important and play a role in what we see in the types of storms that impact California.”
Statewide, electronic readings of snowpack from the DWR have recorded a snow water equivalent of 2.5 inches, which is 25% of the average recorded conditions. Anderson said the average that the state compares the current snowpack to is based on a 30-year average calculated by NOAA and updated every decade.
The snowpack recorded so far this winter is drastically less than what the Sierra Nevada saw last year; Anderson called last year’s wet season an “extreme anomaly.”
In January 2023, the Phillips Station survey measured 55.5 inches of snow depth — 177% of the average — and 17.5 inches of water content. The water content measured on Jan. 2 was just 9% of the average recorded on April 1; last year the water content measured in January 2023 was 68% of the April 1st average.
California typically sees its peak snowpack measurement on April 1, and half of the state’s annual precipitation usually falls in the “big three” months of December, January and February, Anderson said. This means that there is still time to see more precipitation before assuming 2024 will be a drier year.
As winter continues and the DWR gathers more data, they will be able to better understand what the rest of the water year will look like. Schwartz said the UC Berkeley Snow Lab is working on finding ways to model and track how soon snowpack will melt, which will further the state’s ability to plan for floods or droughts.
Media-oriented snow surveys conducted by the DWR occur near the first of the month from January through April; Anderson said the DWR will know more about the season’s overall outlook come the second survey in February.
“We’re only about one third of the way through the big three months, and a lot can change,” Anderson said. “We certainly saw how quickly things changed last year.”