Abstract Station siting for environmental observing networks is usually made subjectively, which suggests that the monitoring goals for the network may not be met optimally or cost effectively. In Antarctica, where harsh weather conditions make it difficult to install and maintain stations, practical considerations have largely guided the development of the staffed and automated weather station network. The current network coverage in Antarctica is evaluated as a precursor to optimal network design. The Antarctic Mesoscale Prediction System (AMPS) 0000 UTC analysis is used for 4 years (2008–12) with 15-km horizontal grid spacing, and results show that AMPS reproduces the daily correlations in surface temperature and pressure observed between weather stations across the continent. Temperature correlation length scales are greater in East Antarctica than in West Antarctica (including the Antarctic Peninsula), implying that more stations per unit area are needed to sample weather in West Antarctica compared to East Antarctica. There is variability in the temperature correlation length scales within these regions, emphasizing the need for objective studies such as this one for determining the impact of current and new stations. Further analysis shows that large regions are not well sampled by the current network, particularly on daily time scales. Observations are particularly limited in West Antarctica. Combined with the shorter temperature correlation length scales, this implies that West Antarctica is a compelling location for implementing an objective, optimal network design approach.