Significant Rain Forecast For Northern California: NWS

SAN FRANCISCO — Bay Area forecasters are tracking potentially significant rainfall impacting the region over the holidays, and the first signs of the wetter turn in the weather could arrive as soon as this weekend.

New outlooks released by the Climate Prediction Center strongly favor above-average precipitation beginning early next week and lasting through at least Christmas. While details in the early forecast are slim, the National Weather Service is asking people to prepare for a likely rainy period, which could impact holiday travel.

More specifics will come into focus over the next few days.

As SFGate reports, forecasters note December has historically been San Francisco's wettest month of the year, averaging more than 4.75 inches of precipitation. Last year, an atmospheric river brought the city its second-wettest day on record on New Year's Eve, measuring nearly 5.5 inches of rain over 24 hours.

The winter solstice arrives on Dec. 21, and forecasts continue to favor a strong El Niño winter —a pattern typically associated with a wetter season for California. So far, the new "water year" has been sluggish, thanks to a dry October and November, prompting a grim initial water supply forecast earlier this month.

"California's water year is off to a relatively dry start," said Karla Nemeth, director of the Department of Water Resources. "While we are hopeful that this El Niño pattern will generate wet weather, this early in the season we have to plan with drier conditions in mind."

Seasonal outlooks released last month continued to favor a wetter-than-average December through February period in California, and new projections are due by the end of the week.

In the short term, a slight chance of rain is in the forecast for Saturday, with more promising odds for moisture starting Sunday.

Forecasters expect the rain will be accompanied by a warming trend, with temperatures poised to run well above normal. The National Weather Service said Tuesday that a few areas could come close to setting record highs by late in the week.