Like in many other countries of the Middle East, flash floods in Jordan have repeatedly caused fatalities and very high property damage over the past 50 years. One prerequisite for minimizing disaster losses is the ability to accurately predict disaster events so that precautionary measures can be taken. CapTain Rain therefore aims to revise and improve current methods and tools for flash flood prediction and prevention in Jordan and develop recommendations for a risk management and early warning system adapted to the needs of the users. Despite their destructive power, heavy rainfall events play a key role in the hydrological cycle of (semi-)arid regions, as they replenish scarce water resources. In the face of increasing drought risk and water scarcity, it is therefore important to capture and retain rainfall. In this context, CapTain Rain is investigating measures for the diversion, retention and utilization of heavy rainfall and for improving heavy rainfall preparedness of the local population. The study is conducted along an urban-rural gradient and includes Amman and Petra. In addition to traditional methods of stormwater retention, storage and utilization, the concept of multifunctional land use for heavy rainfall prevention is explored in urban areas.