A cumulative picture of the nature of the meridional winds during nighttime is shown in Figure 3 for the months of January, February, and March. During this period, on several occasions, the model shows occurrences of reversal in winds during post-sunset hours. The top panels of Figure 3 show the variation in the meridional winds on those nights when they remain equatorward without any reversal towards poleward direction. In contrast, the bottom panels correspond to those nights when there is a reversal in the meridional winds (or a cessation in their equatorward movement). It can be seen in all the plots that the winds are usually poleward in the daytime and their magnitudes start decreasing during sunset time (typically after 18 LT), and turn equatorward after around 21 LT. It can be noted in the bottom panels that there is a reversal of meridional winds wherein a poleward turn of the meridional winds or weakening of equatorward winds is noted during 21 LT - 01 LT, beyond which it turns again in the equatorward direction. As we move from January to March, the magnitudes of equatorward wind increase during post-sunset hours due to climatological effects, so the number of occurrences of the post-sunset wind reversal decreases. In addition, the model output is derived from a free-run simulation, and it is noteworthy that geophysical events, such as sudden stratospheric warming (SSW), did not occur during the winter analysed in the present study. The simulated variations in the meridional winds are thus not driven by the occurrence of SSW. In the following, we will analyse and discuss the meridional winds obtained from WACCM-X to understand the nature of variation of post-sunset electron density/ redline nightglow emissions for several nights to obtain a systematic picture.