Newport Beach is in line for heavy rain, small hail and possible waterspouts as a storm system moves through Southern California Wednesday night into Thursday.
The National Weather Service forecast for Newport Beach calls for a 60% chance of showers Wednesday, Oct. 21, rising to 90% Wednesday night, with thunderstorms possible. Showers continue Thursday, Oct. 22, with an 80% chance of precipitation and thunderstorms possible after 11 a.m.
The storm adds a new layer of risk for a city already bracing for coastal flooding. The Newport Beach City Council declared a local emergency Oct. 20 and activated its Emergency Operations Center (EOC) ahead of king tides expected Oct. 26-28, according to the city's announcement.
National Weather Service meteorologist Carol Ciliberti told Patch there is a 30% to 40% chance of thunderstorms that could bring dangerous lightning, heavy downpours, small hail and waterspouts that could move onshore as weak tornadoes. Ciliberti said short, intense bursts cause the most trouble. "A lot of times what gets us is shorter term, 15- to 30-minute heavy showers," she said.
Sam Zuber, a meteorologist with the National Weather Service in San Diego, said rain could begin in Orange and San Bernardino counties as early as Wednesday morning before spreading by afternoon. Coastal Orange County could receive approximately three-quarters of an inch, Zuber told Patch. The heaviest rain is expected Wednesday night into early Thursday.
The approaching full moon will bring higher tides that, combined with elevated surf, could cause minor to moderate coastal flooding and erosion, Ciliberti said. City officials have warned that recent ocean water levels have been running 18 to 22 inches above predicted astronomical tides, according to NBC Los Angeles. If those conditions persist during the king tides, flooding could be worse than forecasts indicate.
The city identified the Balboa Peninsula, islands in Newport Harbor and other low-lying waterfront areas as particularly vulnerable. Newport Beach maintains 86 tidal valves and 18 pumps to manage rising water, NBC Los Angeles reported.
Councilmember Erik Weigand said the situation could bring "significant concerns with flooding, coastal flooding in our beaches, but also in our waterways and our harbor," according to ABC7.
Municipal crews are reinforcing beach berms, inspecting stormwater infrastructure and positioning sandbags and equipment in flood-prone areas. Free prefilled sandbags are available at three locations: the Corporation Yard at 592 Superior Ave., Marina Park at 1600 W. Balboa Blvd. and temporary Fire Station No. 1 at the East Ocean Front Parking Lot near Balboa Pier. Empty sandbags are available at Lifeguard Headquarters and Newport Beach fire stations while supplies last.
The San Francisco Chronicle reported the National Weather Service placed Orange County at a marginal (level 1 of 4) risk of flash flooding from excessive rainfall Wednesday. The coast from Monterey to Orange County also faces a marginal (level 1 of 5) risk of severe thunderstorms, with wind gusts up to 60 mph and a short-lived tornado among the possible hazards.
The storm is expected to move out of the region by Friday, with drier weather and sunshine returning. Residents can sign up for Newport Notified emergency alerts at NBPD.org.
