regional ensemble

As operational centers move towards ensemble-based probabilistic forecasting, it was critical for the DTC to expand its efforts into this area in order to continue to serve as a bridge between research and operations. Hence, the DTC expanded its testing and evaluation activities to include ensemble systems in 2010. The DTC currently focuses its ensemble testing and evaluation activities on mesoscale ensemble prediction. The goal of this task area is to provide an environment in which extensive testing and evaluation of ensemble-related techniques developed by the NWP community can be conducted such that the results are immediately relevant to the operational centers (e.g., NCEP/EMC and AFWA). The new and innovative ensemble modeling techniques tested and evaluated by the DTC can originate from universities, other testbeds that focus on specific research topics, and research and development wings of other agencies. Planning and execution of the ensemble testing and evaluation activities is closely coordinated with the operational centers. While case studies can provide important information, the majority of DTC ensembles testing and evaluation activities focus on extended retrospective periods. These tests apply appropriate verification metrics for ensemble systems, including the assessment of statistical significance.

Mesoscale numerical weather prediction (NWP) systems are utilized in both research and operational forecasting applications and can generally be configured to suit a broad spectrum of weather regimes. Due to the number of approaches developed and offered by these NWP systems, it is necessary to rigorously test select configurations and evaluate the performance for specific applications. The DTC's Mesoscale Modeling testing and evaluation (T&E) activities largely focus on retrospective forecasts generated by the DTC. In the past, the DTC's Mesoscale Modeling team has focused on WRF-based T&E activities. While the DTC will continue WRF-based T&E activities for the foreseeable future, it has become necessary to broaden the scope of internal T&E activities to include new software frameworks (i.e., NEMS) utilized by the relevant operational centers (i.e., NOAA). This effort is vital for the DTC to continue to serve as a bridge between research and operations and work is on-going on this front. T&E activities usually focus on extensive retrospective time periods in order to provide a robust data set for objective forecast verification, including the assessment of statistical significance, but case studies will also be considered from time to time in order to obtain more detailed information on the performance of a specific NWP technique.