After last week’s atmospheric river and a second fast-moving, spiraling storm passed through the Bay Area on Monday, cloudy skies were set to clear into the rest of the week before another brief rainstorm touches down Thursday and Friday.
A storm swept into the region Monday, not even 24 hours after the last light showers fell along the tail end of an atmospheric river storm, bringing between a half an inch and a inch of rain to many Bay Area cities. After the smaller storm later this week, the weather is expected to be neutral and cool into the Thanksgiving holiday week, with temperatures “copy and paste” from day to day, NWS meteorologist Brayden Murdock said.
The region already has seen three systems go through the area since the start of November.
The weather service reported that between Thursday and Sunday, Mt. Umunhum in the Santa Cruz Mountains received 3.3 inches of rain, Santa Cruz 1.3 inches, Livermore 0.9 inches, Fremont 0.35 inches and San Jose .13 inches. Concord received only .01 inches.
“It’s really fast-moving,” NWS meteorologist Nicole Sarment said of the storm Sunday night.
Moisture from the southern part of the Pacific Ocean touched land about 5 p.m. Sunday, according to the National Weather Service. It was enough to drop light rain primarily in the interior mountains of the North Bay and in the coastal ranges, and with a few areas of drizzle in the East Bay.
The showers reached a crescendo in the early hours of Monday morning as a narrow cold front band passed through the Bay Area around midnight and drenched the region with moderate to heavy rainfall, Murdock said.
“While a lot of folks were in bed overnight, we saw those winds increase, and then we saw that strong rain band come through,” Murdock said. “It kept its strength enough that even the areas that are typically rain shadows, like San Jose, got a good amount of rain out of it.”
Murdock added that, because of the rate of rain the storm was dropping, it “could have caused a lot more problems if it was slower.” The initial predictions of thunderstorms did not end up manifesting, though a low chance lingered Monday evening. Flood advisories were briefly issued for Contra Costa, Alameda, Santa Clara and San Mateo counties in the early morning hours, according to NWS.
On Monday, a low-pressure system sat over the Bay Area, bringing with it on-and-off storms throughout the day, Murdock said. Those storms were spiraling, meaning that they were rotating around with the North Bay at the center, which brought winds blowing in different directions and “not very consistent weather.”
The storm brought 24-hour rain totals of half an inch to an inch in the East Bay, with downtown Oakland measuring 0.67 inch and the Oakland airport measuring 0.61 inch, as of Monday morning, Murdock said. The Berkeley hills measured 0.88, downtown San Francisco saw totals of 0.84 inch, while the San Francisco airport measured 1.31 inches on the Peninsula. San Jose measured 0.39 inch. Ben Lomond in the Santa Cruz Mountains, which usually gets some of the highest rain totals, received 2.21 inches.
A chance of rain was set to last into Monday evening across the region and trail off overnight as the low-pressure system and cold front move out of the region, Murdock said. Though some cloudy skies may last into Tuesday, both Tuesday and Wednesday were forecast to not see any further showers. Temperatures were set to peak in the low 60s and high 50s Tuesday and cool down even further Wednesday.
A weaker cold front is set to arrive in the Bay Area later in the week, bringing with it another chance of showers — but “not a whole lot of rain,” Murdock said. Scattered showers are expected on Thursday and Friday, with temperatures reaching into the upper 50s in most cities.
“This one’s just not going to be as strong as what we saw (Sunday) night,” he added.
Sarment said that no more than three-quarters of an inch is expected anywhere and some places are likely to get only a smidgen, if any. High surf also will return to the beaches on Friday, though the weather service said they will have more specific details of what that may look like as the week moves ahead.
When the cold front departs on Friday, the area will be clear of storms as it enters a “neutral pattern” with “very calm weather” into Thanksgiving week, with even temperatures and any rainfall concentrating in the north, Murdock said. Through the weekend, temperature highs will mostly sit in the low 60s, with some interior areas such as Gilroy warming up a bit more. Coastal cities will likely not warm up past the 50s.
