In this study upper winds (700 hPa) in aerological observations, ECMWFRe-Analysis and ECHAM climate model simulations for the region ofnorthern Germany were analysed.The comparison of observations and climate model simulations shows someremarkable differences for the monthly average wind direction and for thefrequency of determined wind directions.Westerly winds are generally overestimated in the climate model simulations.The largest differences between simulation and observation are found inFebruary and May. The reason for these differences are deviations in themean large-scale pressure and geopotential distribution, respectively.