Record tides breach Southern California coastlines

Water surged onto Southern California streets on Monday morning as record-breaking tides flooded coastal communities. The surge inundated streets from Newport Beach to Long Beach, marking the start of a week where the region faces days of coastal flooding.

In Newport Beach, water from Newport Harbor flowed onto the Balboa Peninsula, flooding businesses in the Balboa Fun Zone. Residents in Long Beach reported similar flooding along Bayshore Beach, Naples, and the Peninsula. Crews worked to pump out knee-high water and reinforce sandbags along the harbor side of the Peninsula.

The San Pedro tide gauge recorded a high of 8.02 feet on Monday morning, breaking the previous record of 7.93 feet set in January 2005. In La Jolla, officials recorded sea levels at 7.75 feet, a figure that sits just below the station record of 7.81 feet set in November 2015.

Chandler Price, a meteorologist with the National Weather Service in San Diego, noted that the current levels are very close to the record. He said that higher tides are expected Tuesday, which could break the La Jolla record. The National Weather Service warned that even higher levels are anticipated on Tuesday, with the highest risk concentrated in Orange and San Diego counties.

A coastal flood warning issued by the weather service remains in effect through Thursday afternoon. The warning states that low-lying property, including homes, businesses, and critical infrastructure, will be inundated. Some shoreline erosion is also expected during the morning hours.

In Los Angeles, Ventura, Santa Barbara, and San Luis Obispo counties, a coastal flood advisory was issued. The advisory notes that isolated damage to structures is possible in the most vulnerable areas due to seawater inundation.

The flooding results from a rare combination of threats. An El Niño pattern is fueling an active eastern Pacific hurricane season, while a marine heat wave and a 20-year astronomical alignment are driving water levels. Total water levels in Los Angeles, Orange, and San Diego counties could exceed 8 feet above the baseline this week.

Record-hot ocean temperatures are causing seawater levels to be 1.25 to 1.8 feet higher than lunar tides alone would produce. At Scripps Pier in La Jolla, surface water temperatures reached around 77 degrees in early August, well above the average maximum of 70 degrees.

Reinhard Flick, a researcher at the Scripps Institution of Oceanography, explained that the tides are exceptionally extreme due to peaks in the 18.6-year lunar node tidal cycle and the 4.4-year lunar perigee tidal cycle. He warned that if big storms emerge during the upcoming king tides around Thanksgiving, Christmas, and Martin Luther King Jr. Day, the coastal flooding risk will worsen.

In Newport Beach, city officials said seawater reached 8.3 feet on Monday, nearly 2 feet higher than expected from the high tide alone. Potential levels could reach 8.5 feet on Tuesday at 9:50 a.m. and Wednesday at 10:28 a.m. Georgia Rios, a spokesperson for the city, said 25,000 sandbags were deployed over the weekend, crediting residents for limiting damage.