Atmospheric River Arrives: Rohnert Park, Cotati Under Flood Watch

ROHNERT PARK AND COTATI, CA — Rohnert Park and Cotati residents were urged to be prepared as an atmospheric river storm began bearing down Thursday on the North Bay and the Bay Area, and is expected to last into Friday, bringing floods and thunderstorm hazards.

A flood watch was implemented for the entire region from Thursday afternoon until Sunday morning. A wind advisory was expected to remain in effect until Friday afternoon.

Gov. Gavin Newsom declared a state of emergency to support storm response in 21 counties, including Napa. Sonoma County was among 13 counties last week where a state of emergency was already declared.

"Widespread wetting rains are expected over the district through Friday as a potent atmospheric river moves over California," the weather service said. "The moderate to heavy rain will bring increased flooding concerns and landslide potential. In addition to the rain, gusty southerly winds will persist through Friday. Winds will be strongest near the coast and higher terrain."

Over 2 Inches of Rain Reported In Sonoma County

Most cities in the Bay Area observed at least a tenth of an inch of rain in the past 24 hours, as of 4 p.m. Thursday. The North Bay has seen the most rainfall, with many cities observing more than half an inch of rain.

By 6 p.m. Thursday, the National Weather Service reported 12-hour rainfall totals of more than 2 inches for several parts of Sonoma County, including Graton, Occidental, Cazadero, Sebastopol, Monte Rio, Bodega Bay and Austin Creek/Russian River.

Rohnert Park received 1.90 inches of rain by 6 p.m., Healdsburg received 1.37 inches and Petaluma received 1.10 inches.

Roadway Flooding Reported In Sonoma County

At 7:48 p.m. Thursday, Rohnert Park Expressway was closed at Rancho Verde Circle due to flooding, the Rohnert Park Department of Public Safety said in a Nixle alert. The public should avoid the area, police said.

Shortly before 8:30 p.m., the Rohnert Park DPS issued another Nixle alert to report that the area of Redwood Drive and Martin Avenue was also closed because of flooding.

Earlier Thursday evening in Sonoma County, the California Highway Patrol reported a rockslide with mud, dirt and rock on westbound River Road just east of state Highway 116; flooding on westbound Occidental Road east of SR-116 and on Hall Road west of Fulton Road in Santa Rosa; a tree blocking northbound Dry Creek Road south of Lytton Springs; and a mudslide with trees attached on Green Hill Road at Graton Road.

There were also reports of roadway flooding on Rohnert Park Expressway at Stony Point Road; roadway flooding at Hales Apple Farm on SR-116; mud, dirt and rock on westbound SR-116 at Martinelli Road; roadway flooding at Olivet Road and Piner Road

Russian River Flood Outlook

Most cities in the Bay Area observed at least a tenth of an inch of rain in the past 24 hours, as of 4 p.m. Thursday. The North Bay has seen the most rainfall, with many cities observing more than half an inch of rain.

According to the National Weather Service, rainfall and snowmelt will lead to rapid rises of area rivers, streams, and creeks. Rivers with the most significant flooding potential are Napa, Russian, Salinas, Pajaro and Carmel.

In Sonoma County, the Russian River was forecast to reach the "monitor stage" of 29 feet Friday afternoon at Johnson's Beach near Guerneville. The river's flood stage is 32 feet. The current forecast indicates the river will crest at 30.9 feet Friday night at Johnson's Beach near Guerneville. Thursday afternoon, the river was at 12.6 feet.

Flooding is not currently expected on the Russian River in Healdsburg. The river is expected to reach 16.7 feet Friday morning, whereas the monitor stage for the Russian River in Healdsburg is 20 feet and the flood stage is 23 feet.

The Napa River near Napa was forecast to reach "monitor stage" of 22 feet Friday morning. The river's flood stage is 25 feet. The current forecast Thursday afternoon indicated the river would crest at 22.1 feet Friday afternoon, according to the California Nevada River Forecast Center.

In preparation for possible flooding, the city of Napa on Thursday closed the Oxbow flood gates along the Napa River at McKinstry street.

"Flooding is an extremely serious concern associated with this AR," the weather service said. "The ground is already saturated and streams/rivers are already swollen. When additional heavy rainfall falls on an already saturated ground the only thing it can do is run off. Streams/rivers will be quicker to flood due to their current capacity."

The City of Rohnert Park issued a storm statement Thursday:

Understanding that this weekend’s storm has a wind advisory for gusts of wind up to 20-50 mile per hour, the City of Rohnert Park and Rohnert Park DPS anticipate our neighborhoods may experience power outages, downed power lines, and fallen trees. To increase your safety, we encourage community members to be “weather-ready” and prepare for the storm by adding essential supplies in the household, such as extra batteries, water and flashlights. In addition, take advantage of city-sponsored free sandbags to avoid flooding or pooling water near your home. Be proactive and avoid damage occurring to the property, by clearing out rain gutters, and removing loose tree debris or outside patio furniture. Last, your Public Works and Rohnert Park DPS is on alert to support the safety needs of this community during the storm.

Always call 911 to report in-progress emergencies.
Non-emergency questions or information may be directed to our mainline at 707-584-2600.

To contact Public Works for debris assistance or to inquire about free sandbags, please call 707-588-3300 or use the website link: https://www.rpcity.org/.../storm_season_information_and...
Free sandbags are located 24/7 at Callinan Sports Center- 5405 Synder Lane, Rohnert Park.

For power outages please contact PG&E: https://www.pge.com/.../emerg.../emergency-preparedness.page

Sign up for Nixle Alerts at nixle.com , or by texting your zip code to 888-777 to opt-in.

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