Since national automatic weather stations were run in dual sets, the algorithm to make multiple sets of data generated by the double automatic stations into one set of data has become an important issue that must be resolved before the double stations are put into operation. This article presents the master and slave law based on the space consistency from the standpoint of the data of “hot spare”, and also presents two data processing algorithms based on revised synthesis method according to spatial consistency difference from basic statistical principles and the angle to ensure that the data are continuous. We evaluate the integrity and differences of the results by the two algorithms using the hourly temperature data from Xiuning Station. Many assessment methods are used including missing rate, the mean of difference values, the standard deviation of difference values, the consistency rate of difference, ultra slip and coarse slip etc. The results show that both of the two algorithms can guarantee the integrity of the data well, and the results of these algorithms are closer to the “true value” and also can reflect the true situation of the atmosphere. Comparatively, however, the result based on the difference between the revised synthesis is better. Finally, the double station observation data collected from Kuche, Anqing and other three stations are used to assess the spatial consistency method which involves the algorithm. It is indicated that this method is effective in general. Especially, it has a better discriminant ability in humidity, pressure and temperature, but is less effective in distinguishing wind speed, which may be affected by local topography or the impact of selected reference stations.