Author(s): Fawaz Alzabari; Emmanouil N. Anagnostou; Xinyi Shen; Giulia Sofia; Qing Yang; Syed Zaidi; Zequn Lin; Patlakas And Chaniotis

Linked Author(s):

Keywords: Flash Flood; CREST; HEC-RAS; Saudi Arabia; WRF

Abstract: Floods remain a significant challenge in Saudi Arabia, particularly in rapidly urbanizing and vulnerable regions like Jeddah, Almadinah, and Jazan. This study extends the demonstration of an operational flash flood forecasting system, initially tested during the severe 24 November 2022 event in Jeddah, to the flash floods that struck Makkah, Jeddah and Madinah in January 2025. The system integrates high-resolution numerical weather forecasts from the Weather Research and Forecasting (WRF) model with a distributed hydrological model (CREST) and a 2D hydrodynamic model (HEC-RAS), providing real-time simulations of rainfall-runoff and floodplain dynamics. In these events, the forecasting system demonstrated a satisfactory level of accuracy in predicting flood timing, inundation zones, and peak discharges. The forecasting system consistently provided early warnings, capturing the spatial and temporal characteristics of the floods with remarkable precision. By applying the system across these diverse flood events, this study demonstrates the robustness and scalability of the approach for managing flash flood risks in both urban and rural settings. The outcomes highlight the importance of integrating advanced meteorological and hydrological models to improve flood preparedness and response in Saudi Arabia. This research underscores the need for continued development of forecasting systems to mitigate the impacts of increasingly frequent and intense flash floods across the Kingdom.

DOI: https://doi.org/10.64697/978-90-835589-7-4_41WC-P1638-cd

Year: 2025