Between June 10 and July 19, 1987, a total of 26 falling spheres have been successfully launched from the And¿ya Rocket Range in Norway (69 ¿N, 16¿N). From precision radar tracking of the sphere trajectories, 26 temperature profiles were derived for the altitude range 50--90 km. A mean profile, calculated from all data obtained, shows the mesopause to be at an altitude of 88 km and at a temperature of 129¿6 K. This mesopause temperature is considerably lower than predicted in some recently developed reference atmospheres. In the middle and upper mesosphere, each of the 26 profiles exhibits a lapse rate close to -6 K/km. These results are compared with parameters obtained previously in winter at the same site. ¿ American Geophysical Union 1989