Heavy rainfall and flash floods are increasingly impacting arid and semi-arid regions, posing serious risks to both human society and ecosystems. This study investigates the meteorological conditions that led to the destructive rainfall and widespread flooding across Iran in late July 2022, using ERA5 data. The event was driven by an interaction between a moisture-laden tropical monsoon system and a southward-advancing upper-level midlatitude trough. This synoptic setup, combined with an intensified upper-level jet stream and enhanced eddy kinetic energy (EKE), contributed to the development and intensification of a surface low-pressure system. The rare westward extension of the Indian Summer Monsoon (ISM) enabled significant moisture transport into southern Iran, while the presence of the midlatitude trough over northern Iran promoted atmospheric convergence and vertical motion. Preceding heatwaves across the Northern Hemisphere may have increased atmospheric instability and moisture capacity, potentially contributing to the severity of the event, though direct attribution remains uncertain. While the precise role of anthropogenic climate change in this specific event cannot be confirmed, the observed dynamics are consistent with broader trends indicating an increase in the frequency and intensity of extreme precipitation events in a warming climate.