Bay Area rivers, creeks expected to rise rapidly due to storm

The powerful “atmospheric river” storm that was expected to begin hitting the Bay Area Tuesday night could cause “rapid and large rises” in many rivers and creeks, resulting in flooding in some areas, the National Weather Service warns.

Weather service forecasters said coastal hills and mountains in the Bay Area “will see prolific rain totals” likely exceeding 8 inches by the end of the storm.

Soils saturated from a string of previous storms over the past six weeks will result in “prolific runoff” across the region, according to the weather service. Rain was expected to develop in the North Bay by Tuesday evening and spread over the entire Bay Area and Central Coast overnight, according to the weather service.

In a Tuesday morning forecast discussion posted online, the weather service wrote that rivers, including the Russian, San Lorenzo, Pajaro, Carmel and Big Sur, will see rapid rises during the storm.

Waters on the Russian River at Guerneville are forecast to rise above flood stage by Friday, according to the weather service. The river, which measured at about 10 feet Tuesday, is projected to reach 33.5 feet, above the flood stage of 32 feet.

In January 2017, waters along the Russian River at Guerneville reached 35 feet and caused widespread flooding to the small town in Sonoma County. By midTuesday morning, only minor flooding was projected, and at least one resident didn’t bat an eye about the prospect of water spilling into the community.

“It comes along with the territory,” said Elise VanDyne, executive director of the Russian River Chamber of Commerce and Visitors Center in Guerneville. “We wear it proudly, in that as you come though our town, you can see flood markers in many different locations. Where it’s been in the peaks and where it is in the lowflooding time.

“We live in harmony with the river. When it goes up, we’re ready to deal with it.”

Many other rivers and creeks were forecast to approach flood stage but remain below flood levels, but that could change, according to the weather service.

Ryan Walbrun, a meteorologist with the weather service, said he expects updated river forecasts to trend higher.

“I think the big thing is how saturated the soils are,” Walbrun said, adding that there’s “no opportunity” for the rainfall to be absorbed.

“Everything is going to run off into smaller tributaries, creeks and streams,” Walbrun said.

Monday afternoon, the weather service issued a flash flood watch for the entire Bay Area, warning that conditions may develop that lead to flash flooding.

The storm bearing down on California is a “classic Pineapple Express,” according to Bill Patzert, a research scientist and oceanographer who retired last year from NASA’s Jet Propulsion Laboratory in Pasadena. “It’s coming from deep in the tropics south of Hawaii aiming right at the West Coast.”

Fears of mudslides prompted Caltrans to close sections of Highway 1, south of Big Sur, in both directions at 5 p.m. Tuesday. One closure is at Mud Creek, near Ragged Point, the scene of a massive landslide in May 2017 in which millions of tons of earth buried the road 9 miles north of the Monterey-San Luis Obispo county line. The second closure is at Paul’s Slide, about 13 miles north of Mud Creek near Lucia.

Tuesday, Santa Clara County issued a road closure alert for Hicks Road between Pheasant and Alamitos roads because of possible landslides. The road may remain closed until next week because of rain.