Based on the need for advanced treatments of high-resolution urban morphological features (e.g., buildings and trees) in meteorological, dispersion, air quality, and human-exposure modeling systems for future urban applications, a new project was launched called the National Urban Database and Access Portal Tool (NUDAPT). NUDAPT is sponsored by the U.S. Environmental Protection Agency (U.S. EPA) and involves collaborations and contributions from many groups, including federal and state agencies, and from private and academic institutions here and in other countries. It is designed to produce and provide gridded fields of urban canopy parameters for various new and advanced descriptions of model physics to improve urban simulations, given the availability of new high-resolution data of buildings, vegetation, and land use. Additional information, including gridded anthropogenic heating (AH) and population data, is incorporated to further improve urban simulations and to encourage and facilitate decision support and application linkages to human exposure models. An important core-design feature is the utilization of Web portal technology to enable NUDAPT to be a “community” based system. This Web-based portal technology will facilitate the customizing of data handling and retrievals (www.nudapt.org). This article provides an overview of NUDAPT and several example applications.