A Climate-Informed Hourly Precipitation Generator Accounting for Thermodynamic and Dynamic Effects

Sub-daily precipitation data are critical for continuous hydrological simulations in urban watersheds characterized by short concentration times. Unlike the widespread availability of daily precipitation data, sub-daily precipitation data are relatively limited due to the expensive monitoring instrumentation for long-term observation and high computational requirements for high-resolution simulations based on convection-permitting climate models. This study introduces a climate-informed hourly precipitation generator built on the method of fragments (MOF) framework, which accounts for both the thermodynamic influence of air temperature and the dynamic effects of atmospheric circulation patterns on sub-daily precipitation characteristics. The proposed hourly precipitation generator is extended to a multi-site configuration to preserve spatial dependencies in the simulated precipitation field. Application to stations across Germany demonstrates the effectiveness of the proposed hourly precipitation generator in reconstructing both the at-site statistical attributes and the inter-site spatial correlations. This approach provides an effective methodology for generating sub-daily precipitation inputs required for continuous hydrological modeling and flood risk assessments.