The Advanced Quantitative Precipitation Information (AQPI) Project: Building a State-of-the-Art Precipitation Observation and Forecast System for the Greater San Francisco Bay Area

The Advanced Quantitative Precipitation Information Project (AQPI) provides supplemental radar observations across the Greater San Francisco Bay Area – specifically, 4 X-band radars (3 already installed) and 1 C-band radar, by the end of 2025. These new radars complement the existing radar network by filling horizontal and vertical gaps in coverage caused by terrain blockage and distance from the existing radars. Additionally, the new radars operate at a much higher spatial and temporal resolution than the existing network. Together, these aspects provide for much more accurate estimation of rainfall rates and improved short-term forecast capability across the area. Local stakeholders and emergency managers can make direct use of the rainfall estimations, both in real time and integrated over various historical periods, as well as the improved forecasts to optimize any number of operations. These include emergency response, water and wastewater management, flood response, aquifer recharge, transportation efficiencies, and more. The data from AQPI radars can also be assimilated into short-range forecast models and used as an improved forcing dataset for hydrology models, especially those predicting streamflow for small and flashy basins across the area. A robust user interface provides data visualization and delivery, and will continue to mature as the program grows. Notably, AQPI represents a unique collaboration amongst local, state, and federal level entities from the academic, governmental, and private sectors.

This presentation will focus on key aspects of the program including an overview of system hardware, software, and the user interface that ties it all together. It will also highlight a case study that demonstrates the value of the AQPI radar precipitation estimates with respect to those of the existing network. And finally, it will describe a vision of the future of this important effort.