Conveying Coastal Inundation Potential Associated with Extratropical Cyclones in the New York City Tri-State Area

Tropical and extratropical cyclones are one of many potential high impact events that Emergency Management (EM) officials in coastal communities have to contend with.  The impacts from storm surge associated with these types of weather systems can prove to be extremely challenging for meteorologists to convey due to several reasons.  The evolution of Geographic Information Systems is making it easier to provide decision makers with the information to move people out of harm’s way.

The National Oceanic and Atmospheric Administration’s National Weather Service has developed several tools to aid an EM’s evacuation decision making process when moderate to major coastal flooding from storm surge threatens their jurisdiction.  Recently, there has been confusion amongst EM officials, the media, government officials and even forecasters on what storm surge is and the extent to which it will affect a community since it can be represented in many different vertical datums.  With the exception of mean sea level, these vertical datums are not widely known by many people outside of the scientific community. Referencing storm surge data to them does not convey the critical nature of the potential hazard so they can prepare accordingly.  Additionally, probabilistic storm surge maps are only produced by the National Hurricane Center when the U.S. coast is threatened by a tropical cyclone.  There have been many extratropical cyclones, that produce moderate to major coastal inundation, but there are limited visualization tools to display where potentially impacted areas would be for these types of storm systems in a way that people can understand.  This project will focus on a process to create dynamic inundation maps, based on the National Weather Service New York, NY total water level forecasts, in feet Above Ground Level across the New York Tri-State area.