Urban flash flooding is a serious problem in large, highly populated areas such as the Dallas-Fort Worth Metroplex (DFW). Being able to monitor and predict flash flooding at a high spatiotemporal resolution is critical to mitigating its threat and cost-effective emergency management. In general, the higher the resolution of the model and the precipitation input is, the better the spatiotemporal specificity of the model output is. Due to the errors in the precipitation input, model parameters and model itself, however, there are practical limits to the resolution of modeling. In this work, we assess the dependence of accuracy in streamflow simulation on modeling resolution using the National Weather Service (NWS) Hydrology Laboratory’s Distributed Hydrologic Model (HL-RDHM) for a large part of DFW. The spatiotemporal resolutions considered range from ~250 m to ~4 km and from 1min to 1 hr. The high-resolution precipitation input comes from the DFW Demonstration Network of CASA radars. The model simulation results are evaluated using the water level observations from the Cities of Fort Worth, Arlington and Grand Prairie in DFW.
Seo, Dong-Jun; Rafieei Nasab, Arezoo; Nazari, Behzad; Norouzi, Amir; Mathew, Thomas; Chen, Haonan; Chandrasekar, V.; and Jangyodsuk, Piraporn, "High-Resolution Flash Flood Forecasting For Large Urban Areas – Sensitivity To Scale Of Precipitation Input And Model Resolution" (2014). CUNY Academic Works.