El Niño is expected to cause the sea level to rise along the coast of California by approximately 30 centimeters by mid-October. This increase is due to a large volume of water being displaced northward from the coasts of Mexico and Central America. The water is arriving in the form of a coastal Kelvin wave, marking one of the first significant impacts of the El Niño event.

This phenomenon is a clear sign that El Niño has reached California, according to an oceanographer. Further details about the effects of El Niño are available from the source.

The rise in sea level could exacerbate the effects of winter storms.