Through a cooperative inter-agency effort, the Departments of Commerce (DoC), Transportation (DoT), and Defense (DoD) are developing a 4-dimensional (x,y,z and t) aviation weather datacube (4DCube) to meet the significantly increased automation and machine-to-machine (M2M) weather requirements of the Next Generation Air Transportation System (NextGen). The 4DCube can de described as a data abstraction that allows one to process aggregated data from a number of perspectives. Each agency will fuse its existing efforts to meet their agency's aviation weather requirements into a mutually supportable national aviation weather datacube. The goal of this focused federal effort is to merge the majority of public and private sector aviation weather needs into the overall air transportation management process. While the USG datacube will satisfy the vast majority of aviation weather requirements, agencies will maintain an independent capability to satisfy agency unique requirements such as homeland defense (DoD), non-aviation weather requirements such as flood forecasting and warning (DoC), and National Air Space (NAS) traffic flow management (DoT). In the end-state, the 4-dimensional weather datacube will benefit from complimentary agency research and development focused on improved numerical weather prediction, aviation hazard prediction/detection, automated decision rules and net-centric weather data standards.