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We analyze the performance of the European Centre for Medium‐Range Weather Forecasts (ECMWF) and UK Met Office (UKMO) meteorological models in predicting offshore blowing wind in coastal areas. Our attention is mainly on the Mediterranean coast, up to 200 km distance from the shore. We compare forecast neutral winds with Advanced Scatterometer measurements. The results indicate that the ECMWF forecasts systematically underestimate wind speed with respect to scatterometer data, while the UKMO model tends to overestimate. A cross‐analysis suggests that, better than fetch, model biases are a function of the model horizontal discretization, hence of the number of grid steps the wind runs over the sea. The steepness and roughness of the land orography before entering the sea, together with the related drag parameters, appear to have a strong role in determining the coastal offshore wind values. Surface drag over land tends to reduce the related wind speed, and it takes a few grid points to adjust to the smooth sea surface conditions. This is supported by a detailed study with a high resolution grid, but different orography resolutions. In these simulations, practically identical coastal wind speed distributions are found when the subgrid orography schemes are switched off. Vertical cross‐sections of potential temperature and wind in bora and mistral conditions illustrate the strong role of gravity waves, wind channeling and turbulent diffusion in coastal numerical weather prediction. Besides local wave modeling, this may be relevant for offshore wind farms, typically situated within 5–50 km from the coast. Plain Language Summary: Practical experience shows that European Centre for Medium‐Range Weather Forecasts coastal wind speeds, particularly when blowing from land to sea, are often underestimated. We have quantified this error by comparing model data with satellite measured ones. The results indicate that surface wind speeds progressively increase the further we go from the coast, reaching the correct values at about 200 km offshore. Analysis of the inner land distribution and related orographic characteristics strongly suggests that the underestimate is associated to the roughness of the surface the winds pass across before reaching the coast. This roughness is strongly dependent on the model resolution. The passage of the air flow over steep orography before reaching the coast leads to gravity waves, that is, vertical oscillations of the main flow, that strongly affect the distribution of the surface coastal winds and the time, and space, required to reach the correct values. Key Points: Meteorological model often underestimates offshore blowing wind speeds. We quantify and explain the reasons for itRather than distance, the number of grid steps off the coast, about 10, is crucial in reaching offshore the correct wind speedsCoastal orography is crucial in determining the underestimate at the coast, with also gravity waves determining the fetch evolution [ABSTRACT FROM AUTHOR]