Jefferson County Online A part of the IAGenWeb and USGenWeb Projects The State of Iowa Climatology

No extended record of climatology of Iowa has been made, yet much of great value may be learned from observations made at a single point. Prof. T. S. Parvin, of the State University, has recorded observations from 1839 to the present time. Previous to 1860, these observations were made at Muscatine. Since that date, they were made in Iowa City. The result is that the atmospheric conditions of the climate of Iowa are in the highest degree favorable to health.

The highest temperature here occurs in August, while July is the hottest month in the year by two degrees, and January the coldest by three degrees.

The mean temperature of April and October most nearly corresponds to the mean temperature of the year, as well as their seasons of Spring and Fall, while that of Summer and Winter is best represented in that of August and December.

The period of greatest heat ranges from June 22d to August 31st; the next mean time being July 27th. The lowest temperature extends from December 16th to February 15th, the average being January 20th -- the range in each case being two full months.

The climate of Iowa embraces the range of that of New York, Pennsylvania, Ohio, Indiana and Illinois. The seasons are not characterized by the frequent and sudden changes so common in the latitudes further south. The temperature of the Winters is somewhat lower than States eastward, but of other seasons it is higher. The atmosphere is dry and invigorating. The surface of the State being free at all seasons of the year from stagnant water, with good breezes at nearly all seasons, the miasmatic and pulmonary diseases are unknown. Mortuary statistics show this to be one of the most healthful States in the Union, being one death to every ninety-four persons. The Spring, Summer and Fall months are delightful; indeed, the glory of Iowa is her Autumn, and nothing can trenscend the splendor of her Indian Summer, which lasts for weeks, and finally blends, almost imperceptibly, into Winter.