Skip to main content
U.S. flag

An official website of the United States government

New research led by Deltares, USGS, and USACE investigates the interplay between tropical and extratropical cyclones in driving coastal flooding along the subtropical Southeast Atlantic Coast of the United States. The research presents a comprehensive flood hazard and impact assessment spanning from Virginia to Florida, offering critical insights into the region's vulnerability to flooding events.

Coastal communities along subtropical coastlines are frequently impacted by both tropical cyclones (hurricanes or tropical storms) and extratropical cyclones (winter storms or typical low-pressure areas). Accurately discerning the relative contributions of these distinct weather phenomena to coastal flooding has long remained a challenge for scientists and policymakers.

In the study, physics-based hydrodynamic modeling skillfully reproduces coastal water levels based on a comprehensive validation of tides, almost two hundred historical storms, and an in-depth hindcast of Hurricane Florence.

Key findings from the study reveal a detailed picture of flood risk distribution across the region. While extratropical cyclones were twice as likely to trigger yearly flood impacts, tropical cyclones emerged as the dominant force during rarer 100-year events, contributing to over half of the regional flood risk. 

As sea levels continue to rise, exacerbating the threat of coastal inundation, the study underscores the inevitability of increased flooding across the Southeast Atlantic Coast, regardless of cyclone type. In particular, densely populated counties such as Miami-Dade and Broward are characterized by heightened flood risk, but the study also identifies flood vulnerability in several less populous counties, where the relative risk of flooding was disproportionately high.


Read the study in Natural HazardsTropical or extratropical cyclones: what drives the compound flood hazard, impact, and risk for the United States Southeast Atlantic coast? 

Chart showing relative flood risk per county as a function of sea level rise
Color-coded relative flood risk per county as a function of sea-level-rise (SLR). Different panels (af) represent different SLR scenarios (no SLR to 300 cm).

Get Our News

These items are in the RSS feed format (Really Simple Syndication) based on categories such as topics, locations, and more. You can install and RSS reader browser extension, software, or use a third-party service to receive immediate news updates depending on the feed that you have added. If you click the feed links below, they may look strange because they are simply XML code. An RSS reader can easily read this code and push out a notification to you when something new is posted to our site.