Finally, a chance of rain.
California’s worrisome dry spell could end next week, the National Weather Service said Friday. However, the forecast remains somewhat uncertain, and precipitation is far from guaranteed.
Meteorologist Mike Kochasic said Sacramento has a 10 percent to 15 percent chance of rain beginning Tuesday night, with the likelihood increasing to as high as 40 percent by Wednesday. There’s a higher chance of precipitation in the Sierra Nevada, with the likelihood rising to 50 percent Wednesday and Thursday, he said.
Kochasic said the storm isn’t expected to produce much snow in the Sierra, where electronic readings show the snowpack is just 27 percent of average. “This system is looking pretty warm at the moment,” he said. “It’s looking like a lot more rain than snow.”
With no precipitation expected the rest of this week, Sacramento is on track for its fourth driest December on record. The city has seen has 0.13 inches of rain this month, and none since Dec. 20. The driest December on record was in 1989, when the city got no rain at all.
Barely eight months after Gov. Jerry Brown declared an official end to the five-year drought, the slow start to the rainy season has created fresh fears about another dry period.
Although November was relatively wet, every major city in California has had less-than-normal rainfall since the “water year” began Oct. 1. Sacramento’s rainfall since October is 40 percent of normal, and the situation gets worse farther south: Fresno is at 12 percent and Los Angeles at 3 percent. Some experts have said the unusually dry weather helped fuel the massive December wildfires that plagued Southern California.
The Department of Water Resources will conduct the season’s first official snow survey next Wednesday at Phillips Station, marking a kind of ceremonial start to the water year. Usually the media briefing about water supplies is handled by the director of the department’s snow survey program, Frank Gehrke, but this time he’ll be accompanied by DWR director Grant Davis, in a move that may reflect the growing anxiety over the state’s lack of precipitation. The last time a higher-up joined Gehrke it was Brown announcing draconian water cuts during the worst of the drought in 2015.
Although precipitation in any form is considered welcome, most experts say a healthy Sierra snowpack is most crucial. The snow acts as a second set of reservoirs, augmenting water supplies long after the rainy season ends.
Much of the West has stayed dry because of a stubborn high-pressure ridge hovering over the coast. The ridge essentially blocks storm systems from bringing moisture to the state. Kochasic said the ridge “is showing signs of finally breaking down.”
Even if the winter remains mostly dry, California does have some cushion. Last year’s record precipitation left most of the state’s major reservoirs in good shape. Shasta Lake, the state’s largest reservoir, is at 114 percent of normal for this time of year. Folsom Lake is at 117 percent. Only Lake Oroville is well below normal, a deliberate response to last February’s emergency that forced the evacuation of 188,000 residents.