What happened
Sea levels along the California coast could rise by up to a foot in the coming days as an oceanic Kelvin wave tied to a developing El Niño surges northward along the U.S. West Coast, Agence France-Presse (AFP) reports.
Oceanographers tracking the pulse of warm water say the wave — roughly two inches high in the open Pacific but thousands of miles wide — piles up as it reaches shallow coastal shelves, pushing water levels six to twelve inches above normal high tides. It is traveling northward at about six miles per hour and is forecast to reach San Diego within about a week before moving up toward Los Angeles and San Francisco.
NASA Jet Propulsion Laboratory scientist Josh Willis told AFP that the Kelvin wave is a classic precursor to a strong El Niño event, which could bring warmer coastal waters and wetter winter storms to California later in the season.
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