Abstract
Results of a statistical analysis of wind data collected in West Africa during the summer of 1974 (GATE) are presented. A comparison of the wind meridional components in Bamako and Dakar shows that the easterly wave velocities at 700 mb during the period 30 August–20 September 1974 are approximately equal to those at 200 mb and that the waves are in phase opposition at these two levels. It is suggested that these wave features are favorable to the existence of cloud system formations which were observed in a greater number during GATE's third active phase than during the two previous phases.