High tides could bring up to 1.5 feet of flooding above ground level to low-lying areas along San Mateo County's bayshore through Tuesday afternoon, the National Weather Service warned in an active Coastal Flood Advisory.

The advisory covers bayshore locations along San Francisco and Monterey bays through 3 p.m. Tuesday, Oct. 13. A separate advisory for San Pablo Bay runs through 4 p.m. Wednesday, Oct. 14.

Tuesday's high tide at the San Francisco gauge is expected to be 1.4 feet above normal at 1:14 p.m. The forecast height of 7.2 feet is measured against a tidal reference level, not above the ground. The NWS noted that up to 1.5 feet of surge is enhancing the astronomical tide. That surge is already included in the forecast height. High tide timing can vary up to 90 minutes along the bay.

The agency said flooding could hit low-lying areas, roads and coastal trails, cut off access to some beaches and cause isolated road closures. Residents should not drive around barricades or through water of unknown depth, the advisory states.

A Beach Hazards Statement is in effect through 10 p.m. Monday, Oct. 12, warning of breaking waves up to 16 feet and an increased risk of sneaker waves and rip currents along the Pacific shoreline in the advisory’s San Francisco, Monterey Bay and Big Sur coastal zones. The NWS urged people to stay off jetties, piers, rocks and other waterside structures and to remain out of the water entirely.

Temperatures are forecast to rise after Tuesday, with some inland Bay Area locations potentially reaching the 80s or 90s by Friday, Oct. 16, Bay City News reported in the Almanac. Those temperatures are a regional forecast, not a specific forecast for San Mateo.

Residents can monitor updated forecasts and tide information at the NWS Bay Area forecast page.