South Asian monsoonal rainfall pattern is changing in recent years, i.e., heavier rain spells are frequent with longer intermittent dry spells. Consequently, urban floods are the new normal over South Asia, which exerts profound impacts on the ecosystem and economy. Although climate change is believed to be the primary driver, local anthropogenic forcings like aerosol loading and urbanization can also be contributing to the changing magnitude and length of these wet and dry spells. We propose to perform unprecedented regional climate simulations at 1-km spatial resolution with prognostic representation of aerosol loading, and land use and land cover changes (mainly urbanization) over Indian sub-continent under present and future climate scenarios. Further, using novel atmospheric-hydrological-hydraulic coupled simulations, the relative impact of aerosols and urbanization on rainfall extremes and urban floods will be analyzed. To understand the heterogeneity in the associated processes and feedbacks, three different urban environments, i.e., hilly, coastal and continental cities will be selected in Nepal, Bangladesh and India, respectively. These holistic experiments are urgently needed for better understanding and prediction of hydro-meteorological resilience and urban sustainability over the region, especially as most of the climate models project a consistent amplification of the extreme weather and aerosols over Indian subcontinent in a warmer future.