In a south wind, coastal upwelling can be observed off the western coast of the Black Sea. In the same area, the hydrological structure of waters is strongly influenced by river runoff, which forms a river plume, and a southward longshore current. The paper studies the evolution of the plume on the northwest shelf of the Black Sea and its interaction with upwelling based on numerical modelling. The impact of upwelling development under the influence of the south wind on plume propagation was studied using a three-dimensional sigma-coordinate numerical model (POM-type) to calculate the circulation in the coastal zone taking into account the river runoff. The calculations were performed for a rectangular region for the cases of both uniform depth and typical water stratification of the northwestern shelf. The last case was sampled for May condition, when, on average, the Danube plume development is maximal. It is obtained that the joint dynamics of upwelling and river plume are closely related to the stratification of coastal waters. In the case of unstratified shelf waters, the thin plume layer enhances upwelling and downwelling on the inshore and offshore sides of the river plume, respectively. The results allowed studying the peculiarities of river water transformation during winds that cause the development of coastal upwelling. Estimates of the time of bottom water rise near the coast under the action of south winds with different wind speeds and shelf water stratification parameters retrieved from numerical modelling data can be used to develop regional upwelling indices based on satellite data on the sea surface temperature and wind speed.