Coastal Storm Surge Analysis: Storm Forcing. Report 3. Intermediate Submission No. 1.3

The Federal Emergency Management Agency (FEMA), Region III office, has initiated a study to update the coastal storm surge elevations within the states of Virginia, Maryland, and Delaware, and the District of Columbia. The area includes the Atlantic Ocean, the Chesapeake Bay, including its tributaries, and the Delaware Bay. This effort is one of the most extensive coastal storm surge analyses to date, encompassing coastal floodplains in three states and including the largest estuary in the world. The study will replace outdated coastal storm surge stillwater elevations for all Flood Insurance Studies in the study area, and serve as the basis for new coastal hazard analysis and ultimately updated Flood Insurance Rate Maps (FIRMs). Study efforts were initiated in August of 2008, and are expected to conclude in 2012. The storm surge study considers both tropical storms and extratropical cyclones for determination of return period storm surge elevations. The historical record of events in the region has been used to reconstruct wind and pressure fields for significant extratropical cyclone events and to develop a synthetic suite of tropical storm tracks and associated parameters to drive the models. This will support the statistical analysis of storm surge return period elevations. This report, the third of three reports comprising the required Submittal 1 documentation, describes development of the wind and pressure fields required for FEMA Region III storm surge modeling. The original document contains color images.