California's mountain snowpack, crucial to summer water supplies, is off to a good start after a wet December.

Manual and electronic snowpack measurements taken Wednesday show that the statewide snowpack was 134 percent of average for the date. This amounts to nearly half – 49 percent – of an entire winter's average snowpack, even though winter officially began only about two weeks ago.

"The snowpack at this point is really good, and that definitely makes life easier for water managers and for fisheries managers," said Tom Gohring, executive director of the Sacramento Water Forum, a coalition of area water agencies that works to manage American River water supplies and habitat. "I am still hoping for more."

California was on the cusp of another drought year heading into this winter. The productive December storms now make that far less likely.

Summer snowmelt is essential to serve the water needs of millions of Californians and millions of acres of farmland. The state's vast network of reservoirs and canals collects the runoff for distribution.

"Given the favorable spot we're in at this point in the season, I'd say the outlook is pretty good. But it's not assured," said Maury Roos, chief hydrologist at the California Department of Water Resources, which conducts the measurements.

He noted that numerous prior winters have dried up from January onward, so a lot depends on the months to come.

January tends to be the state's wettest month. But this year, long-term forecasts don't look promising.

The Climate Prediction Center at the National Weather Service estimated Dec. 31 that all of California is likely to see below-average rainfall in January.

"We're well ahead," Roos said. "But if it stays dry through the middle of January, by then this 134 percent will probably slip to near average."

Even so, the early storms have helped replenish many of the state's major reservoirs: Lake Oroville is at 71 percent of capacity and 113 percent of average for the date, and Shasta Lake is at 73 percent of capacity and 115 percent of average for the date.

Folsom Lake holds 121 percent of average supply for the date and is 60 percent full.

"If the trend continues to be an abundant year, our supply will be more reliable," said Tom Gray, general manager of the Fair Oaks Water District. "From a water purveyor's standpoint, I would really caution the public from getting too excited, and continue to endorse all conservation measures."

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