SAN FRANCISCO (CBS SF) — While it’s too early to sound the alarm, state water officials said Wednesday the first Sierra snow survey came up relatively empty.
One of the driest Decembers in California history has left a snow pack of just 1.5 inches at the Phillips measuring station. That’s the lowest total since 2012 had 0.6 of an inch and the second lowest total since the state began measuring snow at the station in 1964.
Water officials said the average total is generally 11.3 inches for the first measurement. The site has had measurements of 70 or more inches in 1966, 1971, 1972, 1982, 1983 and 1993.
“As we’re only a third of the way through California’s three wettest months, it’s far too early to draw any conclusions about what kind of season we’ll have this year,” Department of Water Resources (DWR) Director Grant Davis said. “California’s great weather variability means we can go straight from a dry year to a wet year and back again to dry.
More telling than a survey at a single location, however, are the DWR’s electronic readings Wednesday from 103 stations scattered throughout the Sierra Nevada.
Measurements indicate the snow water equivalent of the northern Sierra snowpack was 2.3 inches — 21 percent of the multi-decade average for the date. The central and southern Sierra readings were 3.3 inches (29 percent of average) and 1.8 inches (20 percent of average), respectively.
Statewide, the snowpack’s snow water equivalent was 2.6 inches or 24 percent of the Jan. 3 average.
“The survey is a disappointing start of the year, but it’s far too early to draw conclusions about what kind of a wet season we’ll have this year,” said Frank Gehrke, chief of the California Cooperative Snow Surveys Program. “There’s plenty of time left in the traditional wet season to reverse the dry trend we’ve been experiencing.”
California traditionally receives about half of its annual precipitation during December, January, and February with the bulk of the precipitation coming from atmospheric river fueled storms.
So far this winter, an atmospheric high-pressure zone spanning the western United States has persistently blocked those moisture streams from reaching the state. If that zone were to move or break up, storms could deliver considerable rainfall and snow this winter.
Fortunately, California’s exceptionally high precipitation last winter and spring has resulted in above-average storage in 154 reservoirs tracked by the Department.
DWR estimates total storage in those reservoirs at the end of December amounted to 24.1 million acre feet — or 110 percent of the 21.9 average for the end of the year.