On March 20, 1985, two rockets were launched from Sondre Stromfjord, Greenland, into the dusk auroral oval. Three trimethyl aluminium trails were released to measure the neutral wind profiles between 95 and 190 km of altitude at two points separated by 190 km normal to the invariant latitude circles and at a third point separated from the first two by 300 km along the invariant latitude circles. Two barium/strontium clouds were released at 250 km of altitude, extending two of the neutral wind profiles to this altitude. ln the E region the tip of the wind vector traced an ellipse as a function of increasing altitude with maximum wind speeds of 100--150 m/s in the southeastward and northwestward directions. The F region winds were southward with speeds of 100--200 m/s. The zonal wind component between 115 and 140 km of altitude had a horizontal gradient in the southeastward direction, whereas the meridional wind component at the same heights was constant over the spatial extent covered by the measurements. We interpret the observed E region wind field as being part of a gravity wave with a period of 3 hours as estimated from the ellipticity of the wind hodograms. The wind vectors rotated 540¿ clockwise with increasing height, indicating that the wave energy is propagating upward. The Fabry-Perot interferometer at Sondre Stromfjord was first able to detect the F region winds 45 min after the releases and measured winds of 100--400 m/s mainly in the southeastward or antisunward direction. The geomagnetic conditions were quiet, with Kp not exceeding 2 for the 24 hours preceding the experiment. The incoherent scatter radar at Sondre Stromfjord observed a contracted plasma convection pattern associated with positive By and Bz components of the interplanetary magnetic field. Intermittently, a By<0 pattern was observed. We suggest that the observed gravity wave was excited by the temporal variations of the large-scale plasma convection, although a wave source in the mesosphere or below cannot be excluded. ¿American Geophysical Union 1987