There were a huge number of reporting stations in each state that were generally in excellent agreement with one another. (realclimatescience.com)
Even as automatic reporting stations were introduced, the stations had to be close to buildings so the data cable could be run to the display. (wattsupwiththat.com)
Also suggestive is the decline in the number of reporting stations relative to the base period 1950 - 1980. (johnquiggin.com)