This bill establishes a new program within the National Oceanic and Atmospheric Administration (NOAA) specifically designed to improve precipitation forecasts across all timescales. The program's central goal is to advance forecasting capabilities through the research, development, and operational implementation of fully coupled Earth System Models. Key activities include enhancing the understanding and prediction of precipitation extremes, improving the development and management of relevant datasets, and identifying critical observations related to water vapor, oceans, and boundary layers. The program will leverage high-performance computing and emerging technologies like machine learning to refine model predictions for phenomena such as atmospheric rivers and tropical cyclones, supporting research with academic and private sector partners. It also focuses on advancing current and next-generation forecasting models, identifying observational gaps, and improving operational precipitation products for decision support, while mandating coordination across NOAA, engagement with various stakeholders, and ensuring robust data management and accessibility. Appropriations are authorized for the program from fiscal year 2026 through 2030.