Urban boundary layers (UBL) connect the most complex landscapes with the least predictable portion of the atmosphere across multiple physical scales and human impacts. From the human perspective, routine and critical decisions are made regarding health (e.g., air quality), safety (e.g., hazardous spills), and personal preferences (e.g., umbrellas). Scientifically, describing the state of the UBL poses a significant challenge to represent a full spectrum of meteorological forcings and reactions in forms such as heat islands; street canyon winds and turbulence; urban terrain; and transport and diffusion of hazardous substances. From the user viewpoint, the atmospheric states affect many diverse activities and issues such as: emergency response to varied environment, chemical, and public threats; public health concerns due to episodic and chronic air and water quality hazards and extreme weather events (e.g., heat waves); various modes of transportation (e.g., roadways, transit systems) and the built environment due to severe convective and winter storms; energy demand and delivery. The user also addresses planning and preparation for potential incidents or events as well as post-event consequence assessments. Measurements of the state and processes of the UBL are essential to understanding the atmosphere connecting the event with consequences. The transition from science measurements to actionable information products for a particular user in a particular place has many extremely long-term challenges.

Joint Action Groups commissioned by the Office of the Federal Coordinator for Meteorological Services and Supporting Research (OFCM) have developed actionable reports on issues of modeling capabilities for atmospheric dispersion, including “Research and Development Needs and Priorities for Atmospheric Transport and Diffusion.” Additionally, the OFCM conducted and reported the “Forum on Urban Meteorology: Meeting Weather Needs in the Urban Community.” The ideas and recommendations contained in these reports have been the genesis of the Joint Action Group for Joint Urban Test Beds (JAG/JUTB). This JAG is charged with developing a joint agency plan to implement, operate, and sustain urban test beds addressing the integration of the multiple needs and desires of science and user communities.

This paper addresses the status of the JAG/JUTB report and recommendations.