The role of tidal winds between 80 and 100 km is transporting momentum poleward is examined by using meteor wind data collected over 9 years, 1966--1975, at Adelaide, 35¿S. It is shown that there is an annual variation in the momentum flux and that in summer the poloward flux is more than sufficient to maintain the mean zonal flow at these heights in middle latitudes. However, the meridional transport of momentum is insufficient to balance that due to the mean flow. Alternative mechanisms are discussed.