Mother Nature is bringing Sonoma County a soggy Christmas, with rain continuing over the weekend and most of next week, forecasters said.

Today's rain, heavy at times, will be a continuation of Friday's storm, which flooded local streets and snarled operations at San Francisco International Airport.

Sunday's storm is expected to be heavier, bringing total rainfall over the weekend in Santa Rosa to 2.5 to 3 inches, said Austin Cross, a National Weather Service meteorologist.

"It's winter. This is what we get," he said.

Monday looks like the only break in the storms coming out of the Gulf of Alaska, with chilly days in the low- to mid-50s through Friday.

Christmas Day will start out cloudy, with rain likely by noon adding another inch of precipitation, Cross said.

Rain and showers are likely Wednesday through Friday, with the pattern continuing into the new year.

Friday's storm dropped 2.46 inches of rain in Santa Rosa by 4 p.m., bringing the seasonal total to 16.26 inches. Last year at this time, the city had just 4.24 inches of rain.

Cazadero got 5.05 inches Friday, while Cloverdale had 3.61 inches, Guerneville 3.27 inches, Windsor 2.56, Healdsburg 2.5 and Sebastopol 2.12.

Winds prompted SFO to shut down two of the airport's four runways, making the holiday weekend's busiest day a hard one for travelers.

Flights were delayed up to three hours, and about 100 incoming and outgoing flights were canceled, said Dan Dinnocenti, airport duty manager.

Stormy weather also caused flight delays on the East Coast, he said, making Friday "a bad day for flying."

Dinnocenti said he could not predict how airport operations would go over the weekend and advised travelers to check online for the status of their flights.

Flight operations were normal Friday at the Charles M. Schulz-Sonoma County Airport, said Steve Lange, assistant airport manager.

About 11.7 million Californians will travel over the holiday season, a 1.8 percent increase from last year, according to a AAA Northern California estimate.

"For the fourth consecutive year, California has seen a slow, steady increase in travel volume," AAA spokeswoman Cynthia Harris said.

More than 10 million Californians will drive 50 miles or more over Christmas and New Year's, while more than 950,000 will travel by air, AAA said.

An average West Coast road trip will cover about 838 miles, it said.

The latest round of storms pumped the area's two major reservoirs full, with Lake Sonoma's water supply pool at more than 99 percent of capacity by midnight Thursday.

Lake Mendocino near Ukiah had a water supply pool at 107 percent, said Ann DuBay of the Sonoma County Water Agency.

When the water supply pools are topped, the Army Corps of Engineers takes control of the reservoirs to manage the flood control pool, she said.

Both reservoirs have plenty of capacity in the flood control pools, DuBay said.

The Russian River at Guerneville is expected to crest over the weekend at 26 feet, well below the flood stage level of 32 feet, said Brad Sherwood of the Water Agency.

Christmas of last year was "bone dry," Sherwood recalled, and 2012 was designated as a "critically dry year" in February.

March rainstorms "bailed us out," Sherwood said. The Water Agency counts on mid- to late-spring storms to top off the reservoirs, he said.

(You can reach Guy Kovner at 521-5457 or guy.kovner@pressdemocrat.com.)