Daily weather observation records compiled in Springfield, showing barometric pressure, temperature, daily highs and lows, relative humidity, dew point, wind direction and velocity, amounts of sunshine, cloud types, precipitation amounts, and sunset observations. Also includes sums and means of observations, and monthly and annual summaries.

In the years before 1948, written descriptions of unusual phenomena (frosts, halos, heavy precipitation, droughts, auroras, meteor showers, earthquakes, etc.) are often included, as well as narrative accounts of severe storms, and newspaper clippings of weather-related stories. Also included are descriptions and plans of the locations of the recording stations, and information on recording equipment used.

The daily observation records consist of bound volumes, 1879-1948; ledger sheets, 1948-1988; and computer print-outs after 1989. Also included are Means Books, Climatological Records and Local Climatological Data, which summarize and compare weather data on a monthly and annual basis.