SAN FRANCISCO (CBS SF) — Incessant rain from an atmospheric river flowed through the Bay Area overnight and into Thursday before easing somewhat, allowing some residents in Santa Cruz County forced to evacuate from ongoing threats of flooding and mudslides to return.

The National Weather Service said significant rainfall washed over the Bay Area Thursday morning and parts of central California as the Pacific storm systems tracked inland. A flood advisory was extended for parts of Santa Clara, Santa Cruz, Monterey and San Benito counties until 2 p.m.

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Overnight the main activity was centered over the South Bay and Central Coast, with rain rates over the CZU burn area around three tenths per hour, the weather service said.

In downtown Oakland, the recent storm also brought just over an inch of rain while up to 2 inches fell in the Oakland hills, said Roger Gass, a meteorologist with the weather service.

Oakland fire officials reported several storm impacts, including a mudslide on Moore Drive and reports of flooding at undisclosed locations. Other impacts include trees or limbs down, a park fence that fell over and a downed utility wire on Filbert Street.

About 1.6 inches fell at the Livermore Municipal Airport and up to 2.75 inches in the Dublin area. The Livermore area has received only 35 percent of its normal rainfall for the water year.

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There were traffic incidents dotting the Bay Area roadways, including a crash at the Interstate 680/580 interchange in Dublin, a second crash on I-580 between Dublin and Castro Valley, and a crash along southbound 680 before just north of Auto Mall Parkway in Fremont.

Overnight rain led to flooding in Cupertino along Stevens Canyon Road near Stevens Creek County Park, the Santa Clara County Sheriff’s Office said Thursday. Stevens Canyon was expected to be closed for several hours.

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A Flash Flood Watch remained in effect through Thursday afternoon for all wildfire burn scar areas across the region. Mudslides were reported in the burn zone of the River Fire in Monterey County, and at least one mudslide was reported along the Sonoma County in the area of the Meyers Fire.

In Monterey County, people were evacuated in Carmel after the Carmel River overflowed near Carmel River State Beach. The Monterey County Sheriff’s Office ordered the evacuation of the Carmel River Lagoon area, including all roads south of Santa Lucia Avenue and Mission Fields, following a flood warning Thursday morning.

In Santa Cruz County, evacuation orders were downgraded to warnings Thursday morning after some 5,000 residents of in the area of the CZU burn scar were evacuated as a precaution when the storms approached on Tuesday.

Some 7 to 10 inches of rain were expected for the region, designated by forecasters as having a high risk for excessive rainfall through Thursday morning. The weather service said the designation is reserved for rare events where flash flooding is likely to put lives and property in danger.

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In addition to the heavy rainfall, higher elevations were getting hammered with extreme snowfall. Several feet of snow (as much as 10 feet in total accumulation) will be possible for the Sierra Nevada through Friday morning, causing road closures and travel delays.

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In the Eastern Sierra, the Mammoth Mountain ski resort reported 6.3 feet of new snow on its summit.

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Winter Storm Warnings and Winter Weather Advisories blanketed the region, along with Blizzard Warnings for parts of the Sierra Nevada where gusty winds will accompany the heavy snow.