Sonoma County deals with effects of latest atmospheric river
Steady rain began to fall in the North Bay Thursday afternoon, bringing isolated thunderstorms that were expected to continue into Friday morning, according to the National Weather Service.
The sustained downpour caused a series of road closures and flooding in parts of Sonoma County during the evening’s drive home. And was the cause of a mudslide that blocked traffic along Green Hill Road between Graton and Occidental streets near Sturgeon’s Mill, according to Redcom, the county’s emergency response center.
Just after 4:30 p.m., debris blocked both lanes of Green Hill Road, but by 5 p.m. at least one lane had been reopened, a dispatcher said, adding there were no casualties reported.
In Rohnert Park, city workers closed a portion of the Rohnert Park Expressway near Stony Point Road shortly after 5:30 p.m. due to flooding.
And just before 5:50 p.m., there were reports of a fallen tree blocking the westbound lanes of Highway 116 just west of Mirabel Road, according to the California Highway Patrol traffic website.
Around the same time, authorities received reports of aquaplaning cars along Hall Road near Park Royal Avenue in northwest Santa Rosa. According to the CHP website, there was 6 inches of water on the pavement.
Just before 7 p.m., a woman whose car was caught in standing water on Trenton-Healdsburg Road near Riverfront Regional Park was rescued by a rapid water rescue crew from the Forestville Fire Department, part of the Sonoma County Fire District.
Meteorologists predict some areas of the North Bay could see up to 8 inches of rain through Friday night, depending on terrain and where thunderstorms are hit.
Santa Rosa is expected to get about 2 to 3 inches of rainfall.
Warm atmospheric flux began moving through the area in the early afternoon. It is expected to flow south around 10 p.m. and eventually exit San Francisco, said Evan LaGuardia, a weather forecaster with the National Weather Service.
Atmospheric fluxes, long and narrow bands of moisture in the atmosphere, transport water vapor and warm air from the tropics, according to the Weather Service. They typically span thousands of kilometers and shed rain and snow when they land.
The storm was expected to bring light to moderate rain to Sonoma County through Thursday evening. During the night it would gradually become heavier, with a 30% chance of thunderstorms.
During the thunderstorms, rain rates could reach as much as 2 inches per hour, LaGuardia said.
Sonoma County maintains this list of emergency shelters that are open to people who are homeless and are looking for help in the cold and rain.
The Weather Service issued a flood warning for the entire Bay Area and Central Coast through 10 a.m. Sunday, and a wind warning is in effect through 4 p.m. Friday.
Strong southerly winds of 35 to 39 miles per hour are expected at elevations below 900 feet, with gusts of 47 to 57 miles per hour, according to the weather service.
The Russian River has been predicted, according to a chart released by the California Nevada River Forecast Center, operated by the National Oceanic and Atmospheric Administration Thursday afternoon to reach up to a foot above the 15 foot high tide level in Hopland around 8am on Friday.
A crest of the river was predicted in Guerneville Just over a foot above the 32-foot high-tide level Friday night before receding Saturday morning. The forecasts have a significant error rate.
The sustained rains and stronger storms will slow around 11 a.m. Friday, although rains could continue Friday night into Saturday.
Due to the heat from the storm originating in the Hawaiian Islands, there will most likely be no snow outside of points around 8,000 feet in the Sierra Nevada.
Staff writer Jeremy Hay contributed to this report.
You can reach staff member Madison Smalstig at [email protected]. On Twitter @madi.smals.