Abstract <p>The impact of the horizontally inhomogeneous ocean surface temperature (OST) field in the vicinity of a coastal upwelling (belonging to the Eastern boundary upwelling systems) on the regional characteristics of the tangential wind stress field is analyzed. It is shown that the change in the turbulent regime of the near-surface boundary layer of the atmosphere during the transition from the upwelling region with a relatively low OST to a warmer offshore zone is the main mechanism that determines the impact of the horizontal inhomogeneity of OST in the upwelling vicinity on the tangential wind stress and its curl. A conclusion is made that present-day arrays of satellite data and atmospheric reanalyses highly likely underestimate the tangential wind stress curl and its contribution to the total upward movement rates of waters of the subsurface layers in the vicinity of upwellings of the type under consideration.</p>