 Urban development can lead to increased flood risk in cities due to changes in hydrology and meteorology, as well as increased vulnerability caused by urban concentration. These effects are better understood than the relationship between urban growth and floods due to microclimate changes. Climate variability and change could further exacerbate these risks. In the Mekong River Delta city of Kimdo, Vietnam, we simulated future scenarios combining climate-driven sea-level rise, predicted river-level increase, urban growth, and microclimatic changes. Our results suggest that under a combination of these factors, flooding could increase significantly. To mitigate this risk, detailed research into adaptation measures is needed to ensure effective investment. This article was authored by H. T. L. Hong and Apatharana.