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The first observations of mean winds and the amplitude and phases of the tidal components measured with a meteor wind radar located at Trivandrum (8.5°N, 77°E) during five consecutive days of counter electrojet events identified in the horizontal component of the earth's magnetic field from January 27–31, 1987 are described. The mean zonal winds in the altitude region of 90–105 km are in general westward during counter electrojet days and eastward during no counter electrojet days. The amplitudes and phases of the tidal components on the counter electrojet days are found to be substantially different from those on the no counter electrojet days.

The possible penetration of magnetospheric convective electric field to low latitudes is investigated with the help of VHF radar measurements of equatorial electrojet electric fields during the 1054 UT substorm of March 22, 1979. The observed time relationship of these electric fields with the southward component of the interplanetary magnetic field and the polar‐auroral magnetic activity suggests that the magnetospheric convective electric fields may penetrate to low latitudes, at least on certain occasions during the growth phase of a substorm before screening by ring current becomes effective.

Nighttime equatorial thermospheric meridional winds have been derived using h′F data from two equatorial stations nearly on the same magnetic meridian. It is shown that the winds derived are quite consistent with earlier observations.

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