Another in a series of powerful winter storms hits Northern California Monday, raising concerns about flooding and dangerous winds that prompted President Biden to declare a state of emergency.
A series of atmospheric flows that pounded coastal communities last week and left more than 400,000 in California without power on Sunday will be followed by two major episodes of heavy rain and snow in the mountains over the next few days. Rivers are expected to reach flood waters, debris flows could be possible in fire areas and high winds could wreak havoc with the “energetic and moisture-laden parade of cyclones heading straight for California,” according to the National Weather Service.
Late Sunday, Biden approved an emergency declaration for California, authorizing the Federal Emergency Management Agency to coordinate disaster relief efforts and allocate emergency resources, the White House said in a statement.
“We anticipate the worst is yet to come,” Gov. Gavin Newsom said on Sunday. “We are expecting very intense weather [Monday] and Tuesday morning.”
It was already raining heavily over the San Francisco Bay Area early Monday. The region is expected to experience between 3 and 5 inches of rain and gusts reaching up to 45 miles per hour from the weather system. The Sierra Nevada is likely to experience heavy snowfall of more than 6 feet at higher elevations through Tuesday night.
“The cumulative effect of consecutive heavy rain events will result in additional flooding. These include rapid water surges, mudslides and the potential for large river floods. Vulnerable terrain and areas near recent fire scars are most at risk from debris flows and rapid runoff,” according to a Bay Area forecast by the National Weather Service.
Evacuation warnings or orders have been issued in parts of Santa Clara, Alameda, Sacramento, Sonoma, Monterey and Santa Cruz counties, with forecasts suggesting swollen rivers could flood businesses and homes.
The Weather Service issued flash flood warnings Monday for the Dolan burn scar in Monterey County, as well as parts of Santa Cruz, Watsonville and Scotts Valley. The agency also issued flood warnings for the Carmel River at Robles Del Rio in Monterey County and the Russian River in Guerneville.
San Jose officials braced for what may be the worst flooding to hit the San Francisco Bay Area’s most populous city since the surprise Coyote Creek floods of 2017, which displaced more than 14,000 residents from their homes.
Water District officials warned of possible flooding in San Jose on the Guadalupe River near the Tamien station of the Caltrain commuter rail system, which serves the Northern Cross neighborhood, Ross Creek at Cherry Avenue south of downtown, and Upper Penitencia Creek near Berryessa/North San could affect Jose BART station.
The Santa Clara Valley Water District issued an “extreme weather warning” on Sunday. Flooding is possible in Palo Alto, Menlo Park, Sunnyvale, Morgan Hill and Gilroy in the coming days.
The Russian River near Guerneville could reach flood water on Tuesday, according to the California Nevada River Forecast Center.
Flooding along some rivers could occur even after Tuesday’s rains end due to continued runoff, said Brayden Murdoch, a weather forecaster with the Bay Area National Weather Service.
“Some of the peaks will actually be between systems,” he said. “But some of our main rivers in the region, as well as lagoons and deltas, are already quite stressed.”
Evacuation warnings have been issued downstream of two full reservoirs in Santa Clara County: Uvas Reservoir northwest of Gilroy, whose waters flow into Uvas Creek; and Pacheco Reservoir, which empties into Pacheco Creek off Highway 152 — a major route between the San Francisco Bay Area and Interstate 5.
Santa Cruz County evacuation alerts included cities east and southeast of Santa Cruz, including Soquel, Seacliff, Rio del Mar and Watsonville, which borders the Pajaro River.
The Carmel, Pajaro and Big Sur rivers could reach flooding on Monday and the Salinas river on Tuesday. The rising Carmel River prompted officials to issue an evacuation alert along the Carmel Valley.
Alameda County issued evacuation warnings for the hills east of Hayward and Fremont and west of Pleasanton. Sacramento County issued an evacuation order for the Wilton area along the Cosumnes River, whose waters breached New Year’s Eve levees, killing three motorists whose bodies were found in or near submerged cars near Highway 99.
“We’ve seen many reports of mud on the road and fallen trees,” Murdoch said. “We have had some power outages and road flooding, particularly in the areas where heavier rainfall has developed. There is a lot going on with this system.”
https://www.latimes.com/california/story/2023-01-09/california-storm-rain Biden declares emergency as storm takes aim at California