Evaluation of ECMWF's forecasting system for probabilistic urban flood prediction: a case study in Mexico City

Abstract

As the world continues urbanizing, including efforts to forge a new framework of urban development is necessary. Recent studies related to flood prediction and mitigation have shown that Ensemble Prediction Systems (EPSs) constitute a valuable and essential tool for an Early Warning System. However, the use of EPS for flood forecasting in urban zones has yet to be understood. This work has the objective to investigate the potential use of the Operational EPS, issued by the European Centre for Medium-Range Weather Forecasts (ECMWF), for probabilistic urban flood prediction. In this research, a precipitation forecast verification was carried out in two study zones: (1) Mexico Valley Basin and (2) Mexico City, where for the latter, forecasts were compared against real-time observed data. The results showed good forecast reliability for a rain threshold of up to 20 mm in 24-hourly accumulations, with the first 36 h of the forecast horizon being the most reliable. The EPS has sufficient resolution and precision for flood prediction in Mexico City, which represents a further step toward developing a flood warning system at the local level based on ensemble forecasts.

Evaluation of BOLAM Fine Grid Weather Forecasts with Emphasis on Hydrological Applications

“…In this context, López López et al [1] asserted that the Ensemble Prediction Systems (EPS) have good reliability over study areas in Mexico for thresholds of 5-20 mm of rain accumulated in 24 h and manage to adequately represent the mean and 95 percentile of rain accumulated in 6 h for a forecast horizon of 90 h. On the other hand, Apicella et al [2] concluded that precipitation forecasts are affected by relatively high uncertainties, due to the inherent unpredictable nature of precipitation, which is particularly evident over the Italian territory that they studied. Further, Shahrban et al [3] found that there are only a few studies in Australia that have assessed the forecast of precipitation and, by using rain radar observations for verification, concluded that the forecast skill of the Australian Community Climate Earth-System Simulator (ACCESS) needed significant improvement for hydrological modelling applications.…”