SAN MATEO (CBS SF) — A band of intense downpours rolled across the San Francisco Peninsula Wednesday morning, triggering a flood advisory from the National Weather Service as run-off from the saturated hillsides ponded in roadways and flowed into streams and creeks.

Forecasters said the advisory would remain in effect until at least 1 p.m.

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“At 9:55 a.m. Doppler radar indicated heavy rain moving towards the San Mateo Coast,” the weather service said in its advisory. “This will cause urban and small stream flooding.”

Some locations that will experience flooding, forecasters said, included San Francisco, Daly City, San Mateo, Redwood City, South San Francisco, San Bruno, Pacifica, Burlingame, Half Moon Bay and Hillsborough.

Sudden flooding has already proven to be deadly during the current outbreak of stormy weather.

The San Mateo County Coroner’s Office on Monday identified the couple who were found dead inside a submerged vehicle in a flooded underpass in Millbrae during last week’s storm.

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The coroner’s office said said the victims were 63-year-old Rolando Ortigas Glorioso and 62-year-old Susana Glorioso, both of Millbrae.

Authorities additionally confirmed they were a married couple. The pair tragically died last Thursday in floodwaters during the storm that inundated the Bay Area with rain.

A spokesman for the San Mateo County Sheriff’s Office said firefighters responded at about 5:45 a.m. to reports of flooding at Hemlock Ave. and E. Hillcrest Blvd. in Millbrae, where E. Hillcrest passes under Caltrain tracks.

“Upon arrival, they noticed a person standing on the roof of a vehicle. The fire department entered the water to rescue the person in the vehicle. While doing that they realized that there was a second vehicle in the water,” said Sheriff’s Detective Javier Acosta. “So after they rescued the first person, they tried to gain access to the vehicle in the water. However, the conditions changed rapidly and it became too dangerous for the responders. The water was rising very rapidly and they had to retreat.”

Caltrain underpass where two people were found dead inside a submerged car on E. Hillcrest Blvd. between Hemlock Ave. and Aviador Ave. in Millbrae, December 23, 2021. (CBS)

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Acosta said it took several hours for crews to drain water in the area, and once firefighters were able to access the second vehicle they found two people deceased inside.