The National Hurricane Center (NHC) announced ahead of the 2016 hurricane season that it would issue a Potential Storm Surge Flooding Map for certain tropical cyclones that affect the East and Gulf Coasts of the United States. The map product was developed following several years of consultation with emergency managers, broadcast meteorologists and social scientists. The Potential Storm Surge Flooding Map represents the storm surge heights that a person should prepare for, given the uncertainties in the meteorological forecast. The map shows the geographical areas where inundation from storm surge could occur and the heights above ground that water could reach in those areas. The map also shows a reasonable worst–case scenario (i.e., a 10% chance) of the flooding of normally dry land at particular locations due to storm surge.
The Potential Storm Surge Flooding Map is based on the National Weather Service Sea, Lake, and Overland Surges from Hurricanes (SLOSH) model and takes into account: forecast uncertainty in the hurricane track, intensity, astronomical tides, land elevation and wind field. The map does not take into account: wave action, freshwater flooding from rainfall, riverine discharge or flooding resulting from levee failures.
NHC will release the map at the time of the first issuance of a hurricane watch or warning for the East Coast or Gulf Coast of the U.S., generally within 48 hours of the expected onset of tropical storm force winds. The active map will be available via an interactive web viewer and GIS data will also be available at hurricanes.gov/gis.
The NHC Storm Surge Unit is also requesting comments and feedback on the Potential Storm Surge Flooding Map to help improve the utility and accuracy of the product.