This report presents an analysis of the monthly mean zonal wind and the standard deviation of the zonal wind about the monthly mean. The data are presented in tables and the analyses in time (months)-altitude (30 to 60 kilometers) cross-section as well as profiles for selected levels. The variability of the monthly mean zonal wind, 30 to 60 kilometers, is discussed by individual station. Also, there is a discussion of the altitudinal, latitudinal, monthly, and seasonal variations with a designation of four seasons - winter (dominated by westerlies but with occasional easterlies). November through March; spring transition of westerlies to easterlies, April and May; summer (persistent easterlies), June through August; and fall transition of easterlies to westerlies, September and October.