Forty Years of Meteorological Observations for Marietta

The Marietta Register, January 14, 1869

Editor Register: I observe in the Report of the Smithsonian Institute for 1867, a statement of the results of a careful reduction of the Meteorological Observations carried on for forty years at Marietta; first, from 1817 to 1823 by Judge Wood, and afterward from 1826 to 1859 by Dr. S. P. Hildreth. Some of these results are quite interesting.

The mean annual temperature of these forty years is found to be 52°.46. That of the warmest year, 1828, was 35°.38; and that of the coldest, 1856, was 49°.71, showing that the entire range from the coldest to the warmest is but 5°.67.

The years are neither growing warmer nor colder. The mean temperature of the first twenty years does not differ from that of the last twenty years. The same result is apparent if we compare the summers by themselves, and the winters by themselves; the summers and winters of the first twenty years showing the same mean temperature with those of the last twenty.

During all the forty years, the lowest point to which the mercury fell was 23° below zero, at 7 o'clock A.M., January 20, 1852. The highest point reached was 102° at 3 P.M., July 14, 1859. This gives as the extreme range of temperature, the startling amount of 125°.

The greatest fluctuation of temperature is shown to occur in February, and the least in July and August.

Throughout these forty years, the warmest day, on an average, has been July 23d, and the coldest January 15th; while the 14th of April and the 15th of October have had the same temperature as the mean of the whole year.

The average temperature of the 40 springs has been 52°.88; summers, 71°.51; autumns, 52°.78; winters 33°.01.

The winds that most prevail are the north and southwest, while the northeast and east winds are least frequent. In summer, the south wind is most frequent; in winter, the west and northwest.

It is the southwest winds in summer and the southeast in winter that bring rain and snow; while fair weather generally attends northerly winds throughout the year. In summer the easterly winds also bring fair weather, and in winter, the westerly winds.

The average annual quantity of rain and melted snow is 42-1/2 inches; the least amount being 32.46 inches, and the greatest 61.84 inches. June is the month in which most rain falls, and January furnishes the least, whether in the form of rain or snow.

The average number of rainy days in a year is 86. The greatest fall of rain in one day was 4.25 inches on July 3rd, 1844. The largest fall of snow was 15 inches on December 4th, 1833.

R.