SAN FRANCISCO — Across Northern California, crews worked Monday to clear streets of toppled trees and branches and to clean gutters clogged by debris carried by rainwater from a massive storm that caused flooding and rock slides, and knocked out power to hundreds of thousands.

Despite the problems, the rain and mountain snow were welcome in northern California, which is so dry that nearly all of it is classified as either experiencing extreme or exceptional drought. The wet weather also greatly reduces the chances of additional wildfires in a region that has borne the brunt of another devastating year of blazes in the state.

When the storm arrived during the weekend, people joyfully dusted off rain boots and jackets and children stomped in puddles. Social media filled with pictures that showed windshields splattered with droplets of water and single-word posts: RAIN!

Earl Casaclang of San Francisco kept waiting for a break in the rain Sunday to go out and smoke a cigarette.

“It was crazy. I kept thinking it was going to stop, but it just kept going and going,” Casaclang said Monday as he headed to his job as security guard in the Financial District. “We need it to keep raining, but hopefully not that hard.”

The National Weather Service called preliminary rainfall totals “staggering,” including 11 inches at the base of Marin County’s Mount Tamalpais and 4 inches in downtown San Francisco, the fourth-wettest day ever for the 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 local weather office said. “We literally have gone from fire/drought conditions to flooding in one storm cycle.”

Northeast of the San Francisco Bay Area, 5.44 inches fell on downtown Sacramento, shattering the one-day record for rainfall that had stood since 1880.

Pacific Gas & Electric reported Sunday evening that 380,000 homes and businesses lost power, though most had it back Monday.

Justin Mankin, a geography professor at Dartmouth College and co-lead of the Drought Task Force at the National Oceanic and Atmospheric Administration, said the cycle of going from years-long drought to record-breaking downpours is something expected to continue due to climate change.

“While this rain is welcome, it comes with these hazards and it won’t necessarily end the drought,” Mankin said. “California still needs more precipitation, and it really needs it in high elevations and spread out over a longer time so it’s not hazardous.”