​Objectives: The study aims at conducting hydrological analysis of flash floods of Wadi Abdoun basin West of Amman City in Jordan, using Watershed Modeling System (WMS) software.

Methods: The study used the watershed modeling tools and the- Curve Number (SCS-CN) to predict the flash floods based on the historical rainfall storm three nearby rainfall stations.

Results: The results indicated that there is a significant increase in urban areas by about 70% of the total area of the basin. This led to an higher peak flow of the flood hydrograph due to an increase in runoff potential and decreased the time of concentration of the sub-basins to about 4 hours.

Conclusions: The study concluded that higher peak flows are observed at different locations at the study area. The peak floods overtopped the existing hydraulic structures and caused severe damage to the infrastructures in the study area.