Overview

This map illustrates current worst-case coastal storm surge or inundation scenarios and hurricane strike frequency derived from:

• Sea, Lake, and Overland Surge from Hurricanes (SLOSH) models by the National Oceanic and Atmospheric Administration (NOAA)
• 100 and 500 year flood plains from the Federal Emergency Management Agency (FEMA); and
• Hurricane strike dataset from the National Hurricane Center (NHC).

What is Storm Surge Inundation?  The abnormal rise of water generated by a storm, over and above the predicted astronomical tides.

Were the same analytical methods and assumptions used to develop the FEMA flood plain and SLOSH model maps? The FEMA flood plain maps focus on riverine and coastal flooding. The SLOSH model map focuses on storm surge inundation. For a detailed explanation of the differences in approach, read "Two Coastal Flood Inundation Maps" (PDF) (5 pp, 611K, About PDF)

Hurricane Strike Frequency  The NHC maintains a hurricane strike dataset (.xls, 295K) for U.S. coastal counties, including direct and indirect strikes from all hurricane categories during 1900-2009 (last updated February 4, 2010).

Audience

Coastal managers, policy makers, local/regional authorities