Coastal Flood Advisory Alerts San Francisco Bay Area Due to Lunar Tide Effects

The National Weather Service (NWS) has issued a Coastal Flood Advisory for Northern California, specifically targeting the San Francisco Bay Area, effective from 7 PM Monday to midnight Tuesday. This advisory draws attention to the potential for minor flooding along the San Francisco Bay Shoreline and North Bay Interior Valleys, as well as San Francisco County. The forecast suggests that water levels may rise up to one foot above ground level in low-lying areas near shorelines and tidal waterways.

The tidal events are significantly influenced by natural celestial occurrences, including the lunar perigee and the new moon. The NWS notes that when the moon reaches its closest point to Earth, known as the perigee, there are stronger tide-generating forces resulting in higher than normal tidal ranges. Coupled with the new moon phase, these conditions contribute to the increased tidal swings and above-average high tides during the period of the advisory. The San Francisco tidal gauge is anticipated to record a high tide of 6.88 feet MLLW, or 1.04 feet above its normal level, near 9:02 PM Monday. Analysts predict that timing of the high tide might vary across different regions within the Bay Area by as much as two hours.

Impacts of these tidal changes include potential flooding of parking lots, parks, and roads, with drivers advised to exercise caution by avoiding travel through barricades or water of unknown depth. The NWS warns that hazardous travel conditions may necessitate isolated road closures, and residents in flood-prone areas are encouraged to take protective measures for their properties. Precautionary actions include securing loose objects, boarding up low-level windows, and preparing homes to mitigate flood damage.

Safety guidelines emphasize the importance of vigilance, particularly after dark, as flood dangers may be harder to detect at night. Residents are advised to stay informed and ready to act immediately by moving inland if flooding is observed. It is recommended to have an evacuation plan in place and necessary provisions such as water, food, a flashlight, and a portable radio on hand. Additionally, avoiding exposed coastal areas, piers, or rocks during heavy surf is advisable due to the risk posed by sudden large waves.

The geographical scope of the advisory prominently includes areas throughout San Francisco, the North Bay interior valleys, and extends south toward San Jose and north past Santa Rosa up to Cloverdale. However, northeastern regions such as Concord and areas far west of the Northern San Francisco Bay Area are not anticipated to be impacted.

The public is advised to routinely monitor official weather alerts to stay up-to-date and be prepared to take action as the tides rise Monday evening. By adhering to these guidelines and remaining cautious, residents can ensure their safety and minimize property damage during this period of elevated tidal activity.