NAPA (CBS SF) — The Napa and Russian rivers were expected to reach flood stage Sunday and Monday following days of heavy rain, according to CBS 5 chief meteorologist Paul Deano.
The third storm in recent days was arriving Saturday evening and was to continue into Sunday, bringing an additional three to seven inches of rain in higher elevations. The North Bay is expected to see the heaviest rains, according to Deano.
The Napa River is expected to reach flood stage in St. Helena around noon on Sunday, with water at heights of 15.9 feet, and crest around 3 p.m. at 17.8 feet, according to National Weather Service estimates.
In Napa it will crest around 1 p.m., with water at heights of 25.2 feet, and crest around 4 p.m. at 26.7 feet.
Napa city officials said the flooding is expected to occur in a “largely agricultural and minimally developed area” around Oak Knoll Avenue, about five miles north of the city itself.
“At this time, City of Napa projections indicate that Floor Protection Project improvements that have been completed should accommodate the expected water flows, and that the Napa River will remain in its banks in areas south of Lincoln Avenue,” Community Outreach Coordinator Barry Martin said in a statement. “This calculation is based on the fact that Conn Dam still has several feet of capacity before topping the spillway, and on observation of the Floor Project improvements in previous heavy rain events.”
The Russian River will reach flood stage in Guerneville around 2 a.m. Monday morning, with water at 31.7 feet, and crest around noon at 35 feet, the NWS warning said.
The weather service has also issued flash flood and mudslide advisories for the entire Bay Area, but the North Bay and the Santa Cruz mountains are expected to at particularly high risk. Urban flooding is also likely throughout the Bay Area.
Many Bay Area communities were offering sandbags to residents hoping to prepare for flooding, and the California Highway Patrol was warning drivers to expect hazardous conditions.
The California Geological Survey issued a warning this week about landslides and mudslides, noting that they can occur on any sloped surface and are a particular risk during periods of heavy rain.
Residents on slopes or living at the bottom of a slope should check for fresh cracks in the soil, areas of bare soil and water or mud streaming downhill. While large landslides are slow, fast moving debris flows, often called mudslides, move quickly and can be hard to escape.
“If your residence is on or beneath a slope, the most important thing you can do to protect your safety is to avoid sleeping in lower-floor bedrooms facing the slope during periods of heavy rain,” said Chris Wills, who heads the CGS’ landslide mapping program.
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