Frost and Flooding Are Back in the Bay Area Weather Forecast

Parts of the Bay Area woke to clear skies with frost-covered roofs and temps in the 30s Saturday morning—but flooding is back in the forecast. 

King Tides will hit the Bay Area through Monday placing a coastal flood advisory in effect.

Marin is one of the most susceptible areas. The county is bracing for more possible flooding this weekend as tides along the coast are expected to be exceptionally high, county Supervisor Stephanie Moulton-Peters said. 

The biannual tides, known colloquially as King Tides, have been known to cause flooding along shoreline communities and low-lying roads in Marin, closing roads, clogging traffic and, in some instances, flooding houses or businesses.  

The National Oceanic and Atmospheric Administration (NOAA) reports that tides on Saturday and Sunday have the capability of creating flooding. These tides are seasonal and not related to recent storms, the county said.  

Tides are associated with the moon, and the weekend's tides coincide with the new moon and could reach over 7 feet, according to NOAA data. The highest predicted tides will be at Point San Quentin, which will reach 7.08 feet by 11 a.m. Saturday.  

Moulton-Peters advised residents to allow extra time for trips and to avoid driving through any standing water.

Areas prone to flooding during tides include the China Camp area in San Rafael and the Manzanita Park-and-Ride area in Mill Valley.

Icy roads are also a concern. The National Weather Service placed an overnight freeze warning in effect for parts of the North and East Bay down to the upper Salinas Valley, with temperatures forecast between 28 and 32 degrees in some areas. The warning should expire at 11 a.m. Saturday.

Aside from flooding and frost, the weather forecast for Saturday for the greater San Francisco Bay Area calls for sunny skies with highs in the 50s to low 60s. Overnight lows will range from the 30s to the 40s. Saturday night's forecast calls for partly cloudy skies, mostly clear in the East Bay, with lows in the 30s and 40s.