To have a clearer idea of the wind potential in your area, there are major regional trends. Some places are deemed to be windy, some other are not.
For exemple, here in Madagascar, the extreme nord and the extreme south are very windy.
Obstacles are annoying for two reasons. First, it reduce the wind's speed, so it reduce the available energy. Second, it makes a lot of turbulences which harm wind turbines, gets his life reduced and degrades his operation.
Turbulences are for a wind turbine like pothole for a car. In the ideal, a wind turbine is installed 10m higher than obstacles to sidestep the adverse effect.