More light rain fell periodically through the Bay Area on Monday, continuing a pattern that began Friday and ended a nearly month-long stretch without precipitation.

The latest question is: How long will it be before the region starts to dry out again?

“It’s going to be pretty steady ... through [today] into Wednesday,” National Weather Service meteorologist Joe Merchant said early Monday. “We’ll get a little break Wednesday, but then a surface low is going to tap into the atmospheric moisture that will be left over, and there will be another push on Thursday. That one won’t be as impactful.”

The impact of the first storm since Jan. 3 to bring measurable rain to parts of the region outside the North Bay has been significant in some areas and considerably less in others, according to the weather service.

The heaviest rain in the East Bay came in Oakland. At 6 a.m. Monday, the weather service had measured 2.1 inches of rain since it began falling Friday, Merchant said.

Elsewhere, San Francisco received nearly four-tenths of an inch since Friday. San Jose had received .07 inches and Walnut Creek got .7 inches since Friday.

As expected, the heaviest rain fell in the upper elevations of the North Bay. The torrential downpours there over the weekend dropped 11½ inches of rain atop Mount Tamalpais, Merchant said.

He added that the next wave of the the stormy weather again will carry characteristics of an atmospheric river storm and that the rain totals could be heavy. Merchant said the week’s ongoing rain could total 2-3 inches in the East Bay, an inch in the South Bay and 3-5 inches in the upper elevations of the North Bay.

“The upper level trough is driving into our area, and that trough is going to push the moisture south,” Merchant said.

The weather service said excessive runoff from the rains could result in flooding and the combination of wind and moist ground could increase the chances trees could fall. They issued a flood watch from Cloverdale down through Monterey and into Big Sur — including all of the Bay Area — lasting from 4 p.m. Monday through 4 a.m. Wednesday.

In the Sierra Nevada, at least an inch and as many as 3 inches of snow were expected above 8,000 feet and up to 6 inches were anticipated below it. The weather service issued a winter storm warning from 10 p.m. Monday through 10 a.m. Wednesday. Travel conditions were expected to be close to impossible, according to the weather service.

The moisture is expected to continue through Thursday, before the weather service said clearing will start to take place on Friday. By Saturday, sunny weather is expected in much of the region, with temperatures peaking in the low 60s.