Beachgoers and climate observers alike have plenty to keep them engaged this week as a series of weather events team up to bring some of the year’s most dramatic tidal action to the Bay Area.

Known as “King Tides,” the phenomenon occurs when tidal forces maximize as the moon, earth, and sun come into alignment, with the moon nearest to earth and the earth nearest to the sun.

While National Weather Service meteorologists put out advisories for the King Tides to arrive over the New Year’s weekend with peak activity on Sunday, the high water levels were expected to last into Tuesday.

Historically, the tides have brought minor flooding to low-lying areas around San Francisco Bay and the Sacramento-San Joaquin Delta, as well as some sites along the Pacific coast, such as near Elkhorn Slough near Moss Landing.

Children play on the observation pier at Big Break Regional Shoreline in Oakley after it was partially submerged by King Tides on Feb. 9, 2017. Minor flooding is typical for low-lying areas during the high tide event. (Photo by Glenn Gehlke/Bay City News Foundation)

The King Tides tend to be followed later in the afternoons by the lowest low tides of the season, which could mean trouble for boaters in shallow waterways, forecasters said.

Local tidal data forecasts are available online for several coastal and San Francisco Bay locations.

Rain was expected to continue into Tuesday, with about a quarter of an inch expected in San Francisco, according to the National Weather Service. Oakland should receive a tenth to two-tenths of an inch, while San Jose will likely get less than a tenth of an inch, NWS meteorologist Brooke Bingaman said.

Rain fell in the North Bay on Monday morning, with a quarter to a half-inch along the coast and in the coastal mountains of Sonoma and Marin counties. Stockton was expected be on the tail end of the rain event, with late Monday rainfall accompanied by gusty winds, NWS meteorologist Hannah Chandler-Cooley said.

Bay Area temperatures this week will be milder than they have been over the past week, with highs in the 50s to low 60s and lows in the 40s to low 50s, Bingaman said.

A harbinger of climate change

While the King Tides may be an object of interest for casual observers, those who are concerned about climate change can find other ways to become part of the solution here in the Bay Area. One way is to participate in the King Tides Project.

The campaign helps scientists and researchers visualize future sea level by observing the highest tides of this weekend’s event. Bay Area residents can help by sharing photos they may have taken of the shoreline during the King Tides to create a record of changes to the area’s coast and estuaries.

The King Tides Project began 11 years ago as a partnership of state and federal agencies and non-profit organizations. It is now part of a global network of King Tides initiatives along both coasts of the US, Canada, Australia, New Zealand, Europe, and Asia. In California, partners include the California Coastal Commission.

To learn more about the project and how to upload photos via a web browser or with a free app, visit the King Tides website.