King tides hit California today and when combined with high surf can create a dangerous situation at state beaches.
High tide will occur at 8 a.m., according to meteorologist Bill Forwood of the National Weather Service. The service warns of "large surf" and dangerous rip currents through midnight Monday, subsiding through Tuesday.
In southwestern California, "the king tides this weekend coincided with high surf," the NWS said, "including dangerously high surf on the Central Coast."
Central California beaches could have waves as high as 20 feet Monday, the weather service said. There were coastal flooding advisories for some areas.
"The very high tides often cause coastal flooding when combined with high surf. All the hazards of high surf are increased with the added effect of very high tides.”
As of 7:30 a.m., the highest local tide was 6.6 feet at the Port of Los Angeles.
So what are king tides?
Simply put, they are the year's most extreme tides and occur near the solstices.
"An extreme high tide event that occurs when the sun and moon's gravitational forces reinforce one another," according to the California King Tides Project, which since 2010 has documented the tides and any changes in the state's coastline and ecosystems.
Effects of king tides are weather dependent, said Sara Aminzadeh, executive director of the California Coastkeeper Alliance.
"The years when king tides coincide with a storm event are intense and impactful."
The 2014-15 king tides season will bring extreme tides through Tuesday, then again Jan. 19-21 and Feb. 17-19.