At year’s end, Southern California’s precipitation remains above normal

Storm clouds above downtown Los Angeles
Storm clouds hover over the high-rise towers in downtown Los Angeles on a wet December day.
(Kent Nishimura / Los Angeles Times)

Thanks to December storms, much of Southern California will ring in the new year with above-normal precipitation.

Meanwhile, the northern part of the state remains mostly below normal after the first six months of the rainfall season, according to Jan Null of Golden Gate Weather Services.

Northern California’s rainy season got off to a late start, but Southern California’s was a little early this year.

(Paul Duginski / Los Angeles Times)

San Francisco and Crescent City are at 73% of normal to date as of Monday. Sacramento has seen 79% of its normal rainfall, and an eight-station index of measuring locations in the Sierra Nevada north of Lake Tahoe stands at 73% of normal. This is an area that includes the Sacramento, American and Feather rivers, as well as the state’s biggest dams. It is crucial for water customers throughout the state, and in particular for Southern California.

In the southern part of the state, Los Angeles is at 166% of normal. Sandberg, in the mountains near the junction of the 5 Freeway and Highway 138, is at 188% of normal. And San Diego comes in at 211% of its normal to date. Palmdale, in the high desert, has had 129% of normal rainfall, and Riverside, in the Inland Empire, has 118% of normal.

Santa Maria, in Central California, is on the mark with an even 100% of normal.

(Paul Duginski / Los Angeles Times)

Crescent City and San Francisco were among the reporting stations that saw improvement in December; on Dec. 9, they had seen 60% and 64% of normal rainfall, respectively. But the crucial eight-station index of measuring stations in the northern Sierra slipped from 83% of normal to its current 73%. The five stations in the central Sierra measured 68% of normal, down from 84% on Dec. 9, and the six stations in the southern Sierra showed a decline from 82% of normal on Dec. 9 to the current 73%.

There’s no El Niño in the equation this year, but an atmospheric river or two can quickly change everything. California receives 25% to 50% of its annual precipitation from these unpredictable “rivers in the sky.”