In April 2004 the Directors of the Fleet Numerical Meteorology and Oceanography Center (FNMOC), the Air Force Weather Agency (AFWA), and the National Centers for Environmental Prediction (NCEP) signed an agreement defining the concept of operations for operational execution of the Weather Research and Forecast (WRF) mesoscale modeling framework. Under this agreement, NCEP will have primary responsibility for running WRF model windows over the United States, while AFWA and FNMOC will run other WRF windows over the world's "hot spots" or other contingency areas as required by the joint services' unified operational commanders in the field, or by national command authority. As none of the three operational NWP centers above expect to have the computing resources to fully fill all anticipated requirements by themselves, an interagency collaborative effort to pursue Grid Computing is underway. This effort is being coordinated through the Office of the Federal Coordinator for Meteorological Services and Supporting Research (OFCM). Further, as the WRF and Grid Computing concepts develop, they will be expanded to include ocean modeling through the Earth Systems Modeling Framework (ESMF), which will then involve the Naval Oceanographic Office (NAVOCEANO) as well.

Grid Computing can be defined as a hardware and software infrastructure integrating high-end computers, networks and databases from multiple sources to form a virtual supercomputer on which users can work collaboratively. Numerical weather prediction (NWP) is one of the most operationally and computationally demanding applications; it is fully extensible and can consume all available resources. As such, it is an ideal test case for probing the operational limits of Grid Computing. In November 2003, the DOD High Performance Computing Modernization Program (HPCMP) funded a Dedicated Distributed Center proposal to implement a Joint Operational Test Bed for the WRF Modeling Framework. This Test Bed consists of identical IBM HPC suites at FNMOC and AFWA, linked by a high-speed communications circuit. It will expedite the transition of WRF into operations for DoD, allow Navy and Air Force to test various configurations of WRF to meet service-specific requirements, and support research in the emerging field of mesoscale ensemble prediction. In addition, it will offer a unique opportunity to test Grid Computing tools and concepts against the demanding discipline of NWP, and will be used to propose a design for a national operational weather forecasting grid. To establish "proof-of-concept", FNMOC is prototyping the proposed HPC grid using Linux-based PCs.