Kelvin Wave Reaches Bay Area, Raises Sea To Record Levels: What To Know – Patch

Kelvin Wave Reaches Bay Area, Raises Sea To Record Levels: What To Know  Patch

Water levels in San Francisco reached an October record as scientists track an underwater wave that could amplify coastal flooding. SAN FRANCISCO, CA — An underwater wave linked to this year’s powerful El Niño reached San Francisco Bay this week, potentially contributing to unusually high tides and localized flooding along the Bay Area shoreline, according to ocean researchers and the National Weather Service. The phenomenon, known as a Kelvin wave, can raise sea levels across broad stretches of coastline. Water levels in San Francisco climbed above normal over the past two weeks, peaking Sunday at roughly 1.73 feet above tide predictions, according to the National Weather Service. The weekend's high tides broke the record for October, which was previously 1.4 feet above normal, but on Saturday water levels reached 1.62 feet above the normal highest daily tide and on Sunday it reached that 1.73 mark, according to The San Francisco Chronicle.

The National Weather Service attributed the elevated water levels to several factors, including the Kelvin wave, warmer ocean water expanding as it heats, a persistent marine heat wave, climate change and lingering effects from distant storms. The water-level anomaly began easing by Monday, potentially as storm-driven swells subsided. But forecasters are also watching for the year’s highest tides, known as king tides, which are expected around Thanksgiving and Christmas.