A round of heavy rain on Monday from an atmospheric river ushered in the holiday week around the Bay Area.
A flood watch already in place for the North Bay will spread to the rest of the region starting Tuesday morning and be in effect through 10 p.m. Friday, according to the National Weather Service.
Parts of Alameda and Contra Costa counties were under a flood advisory on Monday morning.
On Tuesday morning, light rain will transition to heavy rain starting in the North Bay before extending south into the rest of the region, the weather service said.
The storm will bring moderate to heavy rain of 2 to 5 inches in the valleys and up to 6 to 8 inches in the coastal mountains. Creeks and streams could see rapid rises and standing water is likely in urban areas and on low-lying roadways, forecasters said.
The weather service said thunderstorms are also possible on Tuesday, Wednesday and Thursday.
The California Highway Patrol reported several spin-outs and roadway flooding around the Bay Area on Monday morning, including along State Route 121 at the intersection of State Route 12 in Sonoma County.
A high wind watch will also be in effect for much of the region, from Tuesday evening through early Wednesday morning, with south winds 20 to 30 mph with gusts up to 60 mph possible.
“Very hazardous, impactful winds Tuesday through early Friday along our entire coastline and higher elevations inland with power outages likely,” the weather service said.
Dangerous beach conditions are also expected late Tuesday through Friday along the coast.
