Periodicity in time series of wind direction data

Summary The existence of periods of 24 and 92 hours has been proved on the basis of the analysis of time series of hourly mean wind direction data measured at the meteorological station in Praha-Ruzyn in the period from January to June, 1978. Besides, the closest mutual interdiurnal dependence of wind direction data observed at the climatological observation hour, at 7 a.m., has been proved. A method applicable to analysing time series of wind direction data by means of a computer is described.