Data Assimilation Planning and Development for Global and High-Resolution Regional Numerical Weather Prediction at NCEP/EMC

NOAA’s Next Generation Global Prediction System (NGGPS) effort has provided a framework to drastically evolve numerical weather prediction (NWP) efforts at NCEP/EMC. The first implementation of a non-hydrostatic, FV3-based global forecast system is set to take place in January 2019. The next phase of NGGPS includes an ambitious plan with emphasis on improving data assimilation and model physics. The data assimilation component will include science innovation as well as a transition to the utilization of components from the Joint Center for Satellite Data Assimilation (JCSDA)-led Joint Effort for Data Assimilation Integration (JEDI) project.

Beyond the global assimilation component of NGGPS, there are additional efforts underway to advance the data assimilation components of the high resolution regional systems. This includes the operational HWRF as well as efforts toward an FV3-based regional, convection allowing model (CAM) scale system. On the other end of the spectrum, there are efforts aimed at developing a coupled data assimilation system within the context of a future subseaonal-to-seasonal prediction system. All of these applications will take place under the umbrella of the Unified Forecast System (UFS).

This presentation will summarize and synthesize the various ongoing data assimilation efforts at NCEP/EMC for the UFS. A description of the plan to incorporate and implement JEDI-based components will be provided. A discussion of longer term strategies will be presented. These longer term strategies include an intercomparison of algorithms (hybrid 4DEnVar versus hybrid 4DVar), evolution from weakly coupled to more strongly coupled assimilation (for subseasonal to seasonal applications), testing of a rapidly updating global system, and transition to high resolution assimilation for FV3-based regional systems.