In the context of space weather, we investigate the effect of geomagnetic activity on Earth's thermosphere above the Oukaimeden Observatory in Morocco (geographic coordinates: 31.206°N, 7.866°W; magnetic latitude: 22.77°N) over 3 years from 2014 to 2016. The observatory is equipped with a Fabry‐Perot interferometer (FPI) that provides measurements of thermospheric wind speed. In this study 41 disturbed nights (with SYM‐H ≤ −50 nT, Kp ≥ 5) were identified and analyzed. We have characterized the meridional and zonal winds variability and dependence on the solar cycle, during both quiet and disturbed conditions. We have classified the storm time meridional neutral winds into three types of variation. The first type is characterized by traveling atmospheric disturbance (TAD)‐induced circulation: the first TAD coming from the north and the second TAD being transequatorial, coming from the south. This type of storm with TAD‐induced circulation accounts for 59% of the cases. The second type exhibits only slight discrepancies between the disturbed and quiet night flows. These cases account for 33% of the cases. The third type is characterized by the transequatorial wind in whole the night. This last type accounts for 8% of the cases. Finally, we apply a superposed epoch analysis method on the FPI data, and the effect of each phase of the geomagnetic storm on the wind flow and vertical total electron content VTEC has been quantified.

One of the important phenomena of the equatorial and midlatitude ionosphere is the equatorial ionization anomaly (EIA). It forms as a consequence of the equatorial fountain effect (Appleton, 1946;Martyn, 1947;MITRA, 1946;Schunk & Nagy, 2000), caused by the upward vertical E × B/B 2 plasma drift that elevates the F region ionosphere plasma to higher altitudes over the magnetic equator, followed by diffusion along the geomagnetic field lines, that moves the plasma down and away from the equator, forming ionization crests in both sides of the magnetic equator and an ionization trough over the dip equator. The latitudinal plasma distribution that characterizes the EIA (a trough at the magnetic equator and two crests at approximately ±17° magnetic latitude) is well reproduced by many theoretical models (

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