Christmas forecast calls for cold temps, rain in Sonoma County

Sonoma County residents will go to bed Tuesday night dreaming of a wet Christmas, with rain forecast throughout the federal holiday on Wednesday, according to the National Weather Service.

Rain is projected “pretty much on and off all day,” forecaster Steve Anderson said Sunday afternoon.

This time of the year brings “classic cold fronts,” he said, which are generated in the Gulf of Alaska and ride the jet stream, a ribbon of high-speed air circling the globe approximately 60,000 feet above sea level.

Typically, that causes either a direct hit or the tail end of weather systems being pulled by the jet stream to cross into Sonoma County, he said.

“Historically, on average, (we see) the strongest wind and highest rain between now and mid-February,” Anderson said. “We’re just getting into the wet, windy, stormy period.”

Parts of Sonoma County received more than an inch of rain overnight Saturday and into Sunday morning.

The National Weather Service reported 1.4 inches in Venado, about 11 miles west of Healdsburg. Roughly half an inch was measured at Lake Sonoma. Santa Rosa and Petaluma got about a half inch as well.

At least one roadway flooded in Sonoma County, according to the CHP.

By 3 p.m. Sunday, the heaviest rain had moved out of the area and pushed eastward toward the Sierra Nevada mountains, Anderson said.

The weekend rainfall added to season totals that have surpassed the yearly average up to this point and are more than 2 inches higher than at this point in 2018, despite the later start to the rainy season.

Santa Rosa has received 11.5 inches since October, just above the 11 inches the area usually sees by the end of December. Last year, the tally was just over 9 inches at this point, Anderson said.

“We’re looking good in Santa Rosa,” he said.

After Wednesday’s rainfall, the National Weather Service forecasts a break in the wet weather until Sunday.

High temperatures in the daytime are expected to stay relatively steady around the mid-50s countywide this week, Anderson said. Overnight lows will be in the low to mid-30s, with some freezing temperatures in “isolated pockets” in some of the sheltered valleys around the county.

“It’ll be cooler, but not cold,” Anderson said, “depending on what you consider cold.”

You can reach Staff Writer Yousef Baig at 707-521-5390 or yousef.baig@pressdemocrat.com.