Seasonal variations in the 50-mb. circulation over the Antarctic during 1958 are discussed and the features observed in 1957 are compared with those found in 1958. Both years exhibited similar patterns in the fall and winter seasons but differed somewhat in spring and summer. In 1957, the polar vortex of winter began to weaken in early October and by November 21 a closed anticyclone at 50 mb. encompassed the continent. In 1958, the breakdown of the polar vortex was more gradual and by the end of November the 50-mb. circulation was characterized by an irregular pattern of closed cyclones and anticyclones rather than a dominant anticyclone.