Full Moon Triggers Record Coastal Flooding in Florida and California

Seawater has breached streets and properties in beach communities across California, Florida, and the Carolinas this week. The intrusion marks a severe disruption to daily life and commerce in these coastal zones. Forecasters indicated that conditions may persist into the weekend.

The flooding stems from king tides initiated by the full moon earlier this week. These events occur when the Earth, moon, and sun align, creating heightened gravitational pull. While such tides happen multiple times annually, meteorologists noted specific atmospheric factors intensified this cycle.

In Florida, high pressure systems to the north and low pressure over the Caribbean amplified swells, according to Chris Fisher, a National Weather Service meteorologist in Miami. In California, the ongoing super El Niño warmed ocean waters, increasing sea volume. Roger Gass, a meteorologist at the Bay Area forecast office, identified Kelvin waves as an additional factor. These warm water pulses further elevated sea levels.

Residents of Huntington Beach in Southern California placed sandbags outside their homes on Wednesday to block floodwaters. Some commuters traversed submerged streets using paddleboards and surfboards. Authorities closed sections of the Pacific Coast Highway as tides approached record levels in Orange and San Diego counties.

Further north, the weather service predicted minor flooding in low-lying shoreline areas through Saturday. Gass explained that coastal inundation typically occurs within 90 minutes before and after high tide. In Northern California, peak tides reached 1.9 feet above normal levels.

Most of Florida's Atlantic coast remained under flood warnings through early Friday. Street flooding affected coastal cities in South Carolina, including Charleston and Myrtle Beach. Rip currents were reported as far north as North Carolina's Outer Banks. In Fort Lauderdale, drivers navigating flooded streets beside marinas and hotels struggled to reach venues for a major in-water boat show.

Virginia Key in Miami recorded its highest king tide and third-highest water level in three decades, Fisher stated. He noted that only hurricane events have produced higher levels in that location. The meteorologist described the conditions as historical for a king tide event.