Wind speed is determined by atmospheric conditions and terrain characteristics. Even in areas that are generally windy, local conditions may determine whether your wind resource is adequate or not. Wind speeds increase with increased height above the surface. In general, wind speeds are higher in wide open spaces, along ridgelines and near coastlines, where few obstructions interfere with air movement. Vegetation and land use also affect wind speed. For example, rough surfaces like forests reduce near-surface wind speed.