WRF-LES based Urban Weather Forecast System for Korean Urban Air Mobility

Urban Air Mobility (UAM) is an emerging transportation concept that relies on precise and reliable urban meteorological forecasts to ensure safe and efficient operations. To address this need, a high-resolution urban weather forecast system has been developed as part of the Korean Urban Air Mobility (K-UAM) operating system. This system utilizes the Weather Research and Forecasting Large Eddy Simulation (WRF-LES) model, where nested domains are dynamically downscaled to achieve a 100-meter resolution, enabling precise predictions of fine-scale urban weather and turbulence. To enhance forecast accuracy, the system is integrated with WRF data assimilation, allowing the generation of high-resolution analyses at a high-frequency timescale. The model has been run over an extended period to assess its capability in realistically simulating turbulence characteristics at the UAM testbed in Ulsan, Korea. The simulation results of the forecast system are evaluated using an observational grid installed in the Ulsan area, ensuring the reliability and accuracy of the high-resolution urban weather predictions. Additionally, the initial results of data assimilation using WRF 4D-Var (Four-Dimensional Variational Data Assimilation) will be presented, demonstrating its impact on improving urban-scale weather forecasting. The results demonstrate the system's potential to support safe and efficient UAM operations by providing detailed urban meteorological insights.