More wet, windy chaos
Flood warnings issued across the Bay Area; ‘ it’s going to get very ugly’ in Sierra Nevada
A powerful storm that arrived in California late Sunday was forecast to bring buckets of rain, 60 mph winds, and the potential for widespread flooding Monday to a Bay Area already soaked by the wettest winter in years.
Rivers and reservoirs from Sonoma County to the Santa Cruz Mountains are expected to surge. Residents of the Sacramento Valley, where Interstate 5 flooded over the weekend, were warned to be ready to evacuate. And the people of Oroville will keep an anxious eye on the damaged spillways of the Oroville Dam.
“It’s going to be very wet and very windy over the next 36 to 48 hours,” National Weather Service forecaster Bob Benjamin said.
The atmospheric river is expected to bring at least 1½ inch of rain to the lower parts of Santa Clara, Alameda and Contra Costa counties beginning late Sunday, Benjamin said. The Santa Cruz Mountains could receive 4 to 6 inches of rain from the latest system, and 2½ to 3 inches were expected in the East Bay hills.
A flood warning was expected to last through late Monday night in the East Bay hills, the Santa Clara Valley and Santa Cruz Mountains, along with the San Francisco Bay shoreline.
The Russian River near Guerneville, Alameda Creek near Niles Canyon, and the Guadalupe River in San Jose are being monitored for possible flooding through Tuesday, according to the National Weather Service.
In the small Central Valley community of Vernalis, 10 miles southeast of Tracy, the San Joaquin River crossed the flood stage into the danger stage Saturday night and is expected to stay there through Tuesday.
Sacramento Valley residents who live near waterways or in low-lying areas with a history of flooding were cautioned they may need to evacuate.
“The ground conditions are saturated. We do have standing water in many places already,” said forecaster Karl Swanberg. “This is a very wet system.”
One spot that officials will be watching closely is Anderson Reservoir in Morgan Hill, which on Saturday morning reached maximum capacity and began spilling over for the first time since 2006.
Coyote Creek, which is fed by Anderson Reservoir, has become a torrent. Downstream residents are worried. The reservoir is supposed to be no more than 68 percent full to ease pressure on Anderson Dam, which needs seismic upgrades, in the event of a massive earthquake on a nearby fault.
A high wind warning is in effect for most of the Bay Area through early Tuesday morning.
Motorists and residents are warned to look out for more blocked roadways from felled trees and power lines. Air travelers should brace for flight disruptions throughout the region, according to forecasters. And on the surf front, waves could top 20 feet by Tuesday.
Up in Butte County, Lake Oroville on Sunday had fallen more than 48 feet since last weekend, creating a buffer zone for state water officials and local residents. Damage to the emergency spillway last Sunday forced the evacuation of 188,000 people.
On Sunday, the Department of Water Resources said it was increasing the outflow from the reservoir “in anticipation of forecasted weather conditions.”
The troubled flood control spillways have remained “stable” through the changes, the agency wrote in a release, and the changes were not expected to hamper construction and debris-removal efforts below the spillway.
The storm also figures to dump heavy snow in the Sierra Nevada. A winter storm warning will extend into Monday, with 2 to 5 feet expected to fall above 7,500 feet, 8 to 24 inches between 6,500-7,500 feet, and up to 6 inches below 6,500 feet.
“It’s going to get very ugly up there,” Benjamin said. “If you’re up there, OK. If not, I wouldn’t go.”
Bay Area law enforcement officials warned people to check the tread on their tires and to slow down. They also advised people not to drive, bike or walk through flooded areas and to stay off the roads whenever possible.