Numerical simulations are made to study the behavior of atmospheric tides in an atmosphere with arbitrary distribution of mean temperature and zonal wind. Owing to their importance at meteor heights the parametrization of diffusive processes is discussed, and two kinds of models are used, depending on the particular mode studied. Specific attention is given to the (1, 1) mode of the diurnal tide because we want to take into account the modification of its latitudinal-vertical structure due to the background atmosphere. Simulations of semidurnal and diurnal tides are presented and compared with previous theoretical results and eperimental data. However, our main goal is an improved theoretical decription of the diurnal tide. In particular, (1, 1) mode ''distortions'' due to mean wind are shown to be important in accounting for the seasonal variation of the amplitude of the diurnal tide existing in experimental data. The action of turbulent diffusion on the diurnal tide in our numerical results is also analyzed.