Real-time flash flood forecasting for the Dallas-Fort Worth Metroplex (DFW)

Given the high population density, high-resolution observing and modeling capabilities are necessary for prediction of flash floods in urban areas. Continuing urbanization and climate change put such areas in a particularly vulnerable position where even a small-scale but intense rainfall event can cause deadly flash floods and extensive damages. For high-resolution observing and modeling of large urban areas, the use of weather radar and distributed hydrologic modeling is a natural progression. High-resolution modeling, however, is subject to nonlinear growth of error due to errors in quantitative precipitation information and in model states, parameters and structures. Widely varying imperviousness in land cover, and density and capacity of storm drain networks present additional challenges. In this presentation, we describe the ongoing effort for real-time flash flood forecasting in DFW using the CASA (Collaborative Adaptive Sensing of the Atmosphere) radar network, integrative sensing and prediction of urban water, and the potential role of data assimilation in bridging the information gap.