Coastal Flooding: San Pedro Tide Gauge Sets New Record

The San Pedro tide gauge recorded a water level of 8.02 feet on Monday morning, surpassing the previous record of 7.93 feet established in January 2005. This measurement occurred as high tides inundated communities across Southern California, causing street flooding from Newport Beach to Long Beach.

In Newport Beach, water surged from Newport Harbor onto the Balboa Peninsula, affecting businesses in the Balboa Fun Zone. Residents in Long Beach reported flooding along Bayshore Beach, Naples, and the Peninsula. City crews worked Monday to pump out knee-high water and reinforce sandbags along the harbor side of the peninsula. Officials stated they had not received reports of significant widespread damage despite the high water levels.

Georgia Rios, a spokesperson for the city of Newport Beach, attributed the limited damage to community preparation. She noted that approximately 25,000 sandbags were distributed over the weekend. Rios stated, "We really saw the community come out. So I think a lot of the success of not having immense amount of flooding damage is due to residents taking part and grabbing sandbags for their homes."

Officials in Orange and San Diego counties have issued a coastal flood warning valid through Thursday afternoon. The National Weather Service predicts low-lying property, including homes and businesses, will be inundated, with shoreline erosion likely in the morning hours. A coastal flood advisory is in effect for Los Angeles, Ventura, Santa Barbara, and San Luis Obispo counties, where isolated damage to vulnerable structures is possible.

Chandler Price, a meteorologist with the National Weather Service in San Diego, reported that sea levels in La Jolla reached 7.75 feet on Monday. This level is close to the station record of 7.81 feet set on Nov. 25, 2015, during a strong El Niño event. Price indicated that higher tides expected on Tuesday could break the La Jolla record.

The National Weather Service office in Oxnard projects that seawater levels at Los Angeles Harbor could reach 8.1 feet on Tuesday and 8 feet on Wednesday. The current record for that location is 7.92 feet, recorded on Jan. 10, 2005. In Newport Beach, water reached 8.3 feet on Monday, a level nearly two feet higher than expected from the high tide alone. Officials project potential seawater levels of 8.5 feet on Tuesday at 9:50 a.m. and Wednesday at 10:28 a.m.

Scientists identify a combination of factors driving the high water levels, including an active eastern Pacific hurricane season fueled by El Niño, a marine heat wave, and a rare astronomical alignment occurring once every 20 years. Record-hot ocean temperatures are raising seawater levels by 1.25 to 1.8 feet above what is expected from lunar and solar movements alone. Reinhard Flick, a researcher at the Scripps Institution of Oceanography at UC San Diego, noted that upcoming king tides around Thanksgiving, Christmas, and Martin Luther King Jr. Day will be exceptionally extreme due to peaks in the 18.6-year lunar node tidal cycle and the 4.4-year lunar perigee tidal cycle.