NOAA’s Rapid Refresh Forecast System development includes plans to utilize high-resolution ensemble analysis methods to initialize forecasts. Traditionally, the design process for convection-permitting ensemble forecast systems has been largely ad hoc. More recently, teams that include collaborations between NCAR and NOAA have identified a simplified forecast system design approach that can use a single-physics modeling system based on the UFS short-range weather application. A key benefit of this approach includes a simplified code repository and workflow, but challenges remain to achieve both skillful and reliable predictions. Here, we present highlights from several activities contributing toward convection-permitting ensemble forecast system design, including: i) tools to trace sources of systematic model error to individual model components, such as specific physics packages; ii) approaches to reduce systematic errors in continuous cycling by increasing analysis system resolution along with large-scale analysis blending approaches; iii) diagnosing scale dependent perturbation growth rates within ensemble forecasts; and iv) post-processing methods to enhance the use and usability of ensemble forecasts. Collectively, these activities help guide forecasts system development within NOAA. During the presentation we will also touch on plans to extend systematic model error detection toward situation dependent errors within the global UFS medium range weather application.
