Forecast System Development Activities Toward a Convective-Scale Ensemble for NOAA

Convection-permitting ensemble forecast system design remains largely ad hoc, thus guidance on how to extract skillful and reliable ensemble forecasts for short-range, high-impact weather prediction applications is sorely needed. Balancing computational costs, performance, and meeting the necessary cadence of product deliveries demands an assessment of the relative merit and expense of numerous system design permutations. A team from NCAR, NOAA/GSD and NOAA/EMC are collaborating to test several components of high-resolution ensemble analysis and forecast system design to develop essential guidance for future Rapid Refresh Forecast Systems envisioned by NOAA. Highlights from experimental forecast system design tests in recent testbed demonstrations will be shared. Presented results will focus on identified strengths and weaknesses of our experimental forecast system for high-impact weather forecast applications. Further, progress in select development activities will be shared, such as in creating a high-resolution ensemble analysis over the conterminous United States, model error detection using data assimilation with time-averaged physics tendency diagnostics, or horizontal grid spacing sensitivity.