Weekend Storm Closed Roads, Downed Trees Across Peninsula: See

SAN MATEO COUNTY, CA — Sunday's rainstorm resulted in around four times the average amount of incidents across San Mateo and Santa Cruz counties logged by Cal Fire CZU.

Firefighters responded Sunday to downed trees all over the Peninsula, as well as a pole fire after a tree collapsed on Canada Road in Redwood City.

It's "been a memorable past 24 hours for the Bay Area as the long-talked-about atmospheric river rolled through the region," the National Weather Service said before dawn Monday. "We literally have gone from fire/drought conditions to flooding in one storm cycle."

Several streets in the cites of San Mateo, South San Francisco and San Bruno were closed due to flooding. Traffic lights were out in Pacifica on Monday morning.

In Los Altos, a tree collapsed on a passing vehicle, crushing it. No one was hurt in the incident, according to the Santa Clara County Fire Department.

San Francisco saw its wettest October day ever and its fourth-wettest day overall since the Gold Rush, according to the weather service. The storm was dubbed both an atmospheric river and bomb cyclone.

Several streets in Millbrae were completely flooded, according to ABC 7.

Pescadero saw significant flooding Monday morning, with the water over the road a foot deep at Pescadero Creek Road at Bean Hollow Road.

In the Highlands on Lexington Drive, firefighters assisted with a flooded garage.

Atmospheric rivers are "relatively long, narrow regions in the atmosphere — like rivers in the sky," according to the National Oceanic and Atmospheric Administration. A bomb cyclone occurs when a storm experiences bombogenesis, meaning it rapidly intensifies over a 24-hour period, according to NOAA.

But by Monday morning, the rain had stopped, and the sun peaked out from behind the clouds.

"That sunshine never looked so good!" the city of San Mateo tweeted.

See More: 14 Images Of California's Powerful Storm: Flooding, Debris & More