The year of rain....

Downtown San Francisco records 1 inch of rain in 2 hours amid downpour

By Amy Graff

The National Weather Service’s downtown San Francisco gauge recorded 1.09 inches of rain in the past two hours, weather service forecaster Alexis Clouser said at 3:30 p.m.

“That’s a decent downpour,” Clouser said.

The weather service issued a flash food watch at 2 p.m. as a heavy rain band dumped torrential precipitation.

“The rain band seems to be moving through, so we expect that to expire” at 4 p.m., Clouser said.

Feb. 20, 2:45 p.m. The National Weather Service issued a flash flood watch for San Francisco just before 2 p.m.; the warning remains in effect until 4 p.m. The weather service advised motorists not to drive through flooded waters on city streets.

The warning came after a band of rain dumped torrential precipitation over the city. By 2:30 p.m., weather service forecaster Alexis Clouser said the worst of the rain was likely over for San Francisco and the main rain band was over the East Bay. 

The flash flood warning came on a day when the weather service said there’s a chance for thunderstorms and heavy downpours across the region. 

The stormy weather is not over yet.

While rains diminished Tuesday morning, they’re expected to pick up this afternoon with scattered showers and thunderstorms in the forecast into the evening, the National Weather Service said.

“We still have a few cells out there, we’re looking at more widespread rain this afternoon,” Brayden Murdock, a forecaster with the weather service, said. “As far as rain rates go we’re looking at light to moderate, so not as impactful as what we saw yesterday.”

The chance for thunderstorms is about 25% on Tuesday, Murdock said. Thunderstorms could bring lightning and small hail and kick up strong wind gusts.  

“Localized flooding remains a concern for areas that experience heavy rainfall,” the weather service said in its forecast.

The Bay Area remains under a flood watch through 10 a.m. Wednesday morning, with shallow landslides and rises on creeks and streams possible. 

Drizzly rain is in the forecast Wednesday morning, but conditions are expected to dry up Wednesday afternoon. Dry weather is forecast Thursday, with the chance for rain returning as early as Friday morning.

“It’s not looking like very impactful rain,” Murdock said. “It will start Friday morning and then we’ll have off-and-on chances of rain going into next week, but not as bad as what we saw last weekend.”

The storm that’s exiting the region brought significant rainfall over the weekend and into Presidents Day. Locations across San Francisco picked up 0.5 to 1.25 inches from Saturday morning to Tuesday morning, Murdock said. Santa Clara County recorded 0.5 to 1 inch, with some locations in the hills measuring 1.5 inches, while Berkeley and Oakland recorded 1 to 2 inches. The North Bay saw the most rain, with Sonoma Valley recording 3 to 5 inches.

Murdock said a severe thunderstorm was reported in Napa County on Monday night, and there were reports of a thunderstorm in San Mateo County.