U.S. high tide flooding continues to break records

The 2023 Annual High Tide Flooding Outlook documents high tide flooding events from May 2022 to April 2023 at 98 NOAA tide gauges along the U.S. coast. It also provides a flooding outlook for these 98 locations through April 2024 and decadal projections out to 2050.

High tide flooding is becoming increasingly common due to continued sea level rise, driven in part by climate change. It occurs when tides reach anywhere between 1 to 2 feet above the daily average high tide, depending on location. As sea level rise continues, it no longer takes severe weather to cause disruptive flooding along the coast.

“Communities across the country are seeing more and more high tide flooding, with damaging effects to transportation systems and infrastructure — particularly in our most underserved communities,” said Jainey Bavishi, assistant secretary for oceans and atmosphere and NOAA deputy administrator. “With sea level rise and a strong El Nino, NOAA’s forecasts are a critical resource for our nation’s communities as they plan and take proactive action to build their climate resilience.”

U.S. coastal communities saw a record-breaking number of high tide flood days in 2022 at three stations. On the Southeast coast, Trident Pier, Florida, saw 16 days, two more than in 2020, and Vaca Key, Florida, saw two days, one more than in 2017. In the Caribbean, Magueyes Island, Puerto Rico, saw two days, which increased from one event in 1998.

Five locations tied their previous records. On the Mid-Atlantic, Kiptopeke, Virginia, tied its 1997 record, with 11 high tide flood days observed. Along the Southeast coast, Fort Pulaski, Georgia, observed 13 days, tying its 2019 record, while Fernandina Beach, Florida, observed nine days, tying its 2015 record. On the eastern Gulf, Naples, Florida, tied its 2017 record of three days. On the West Coast, Port Townsend, Washington, observed 13 flood days, tying its 1982 record.

NOAA predicts that from May 2023 to April 2024 the U.S. will experience between four to nine high tide flood days — an increase from last year’s prediction of three to seven days and about three times as many than typically occurred in 2000.

This year, the expected strengthening of El Nino could further amplify high tide flooding frequencies along the East and West coasts. Communities on the Mid-Atlantic and Gulf coasts are expected to experience the most high tide flooding, as El Niño conditions will compound the effects of sea level rise in some areas.