Summary (tl;dr)

Coastal flood advisories are currently in effect for parts of California, particularly the San Francisco Bay Area, due to unusually high tides expected to cause minor flooding and hazardous beach conditions. These events are becoming more frequent globally, partly due to rising sea levels exacerbated by climate change.

Essential Background

A coastal flood advisory is issued by the National Weather Service in the United States when minor coastal flooding is imminent or occurring, which may pose a nuisance but not a serious threat to life or property. This type of flooding typically results from factors such as higher-than-normal astronomical tides and storm surges. However, the baseline for these events is steadily increasing due to global sea-level rise.

The Full Story

Currently, a coastal flood advisory has been issued for the San Francisco Bay Area in California, effective from Tuesday, December 2nd, through Sunday, December 7th, 2025. The advisory warns of up to 1.4 feet of inundation above ground level in low-lying areas near shorelines and tidal waterways. This is expected to lead to the flooding of lots, parks, and roads, with only isolated road closures anticipated. Additionally, hazardous beach conditions are forecast along the Pacific Coast, including dangerous sneaker waves, strong rip currents, and large breaking waves, posing risks to beachgoers. These conditions are primarily attributed to a period of unusually high tides.

Why It Matters

The increasing frequency of coastal flood advisories is a significant concern, directly linked to the impacts of climate change, particularly rising sea levels and more intense storms. Global average sea level has risen significantly since 1880, and this rate is accelerating due to melting ice and thermal expansion of warmer ocean water. As a result, coastal communities worldwide are experiencing more frequent flooding, even during less extreme tides or on sunny days. This "nuisance flooding" can lead to frequent road closures, reduced stormwater drainage capacity, deterioration of vital infrastructure, and saltwater intrusion into drinking water supplies. Experts project that by 2050, a majority of U.S. coastal areas could face 30 or more days of flooding annually, with the overall impact of coastal flooding projected to increase fivefold this century, putting millions more people at risk.

Geographic Location

• San Francisco Bay Shoreline, San Francisco County, California, United States (coastal flood advisory due to high tides)
• Northern Monterey Bay, Monterey County, California, United States (coastal flood advisory due to high tides)
• Big Sur, Monterey County, California, United States (hazardous beach conditions including sneaker waves and strong rip currents)
• San Pablo Bay Shoreline, California, United States (coastal flood advisory due to high tides)
• North Bay Interior Valleys, California, United States (coastal flood advisory due to high tides)
• Pacific Coast beaches, California, United States (hazardous beach conditions including sneaker waves, strong rip currents, and large breaking waves)