Climate Of Chicago - Illinois State Climatologist

Here is what they said about the climate of Chicago in 1913:

“The city is located in latitude 41 35′ North, somewhat less than half-way from the equator to the pole, on a crescent-shaped plain about 581 feet above mean sea level. This plain at its highest point is considerably less than 100 feet above the surface of the lake, and its greatest width is approximately 15 miles in a northeast-southwest direction. The whole plain is bordered inland by a glacial moraine which rises in places to about 150 feet above the higher portions of the plain itself. This rim is far too low to exert any appreciable effect upon the climatic or weather conditions of the city, and forms no barrier to either cold-wave areas from the west or hot winds from the southwest and south. Such barrier, however, is but infrequently needed, as many times the waters of the lake serve to soften the rigors of the wintry storms or moderate the intensity of the summer’s heat.

Located as it is at the southwest corner of the lake, Chicago is justly proud of its climate. As a consequence of the cool expanse of water in summer, the city often enjoys delightful and refreshing breezes while the interior of the country away from the lake is sweltering in an air hot and still almost to the point of suffocation. The city is close to certain well-defined storm tracks, and the passage of these disturbances insures ample precipitation and interrupts the otherwise monotonous cycles of temperature and weather change. Chicago has been called the “Windy City” and the ensuing pages will show that there is some reason for the sobriquet, although the wind movement here is not much greater than it is at other places in the Great Lakes region. Its changes in weather are often sudden and pronounced, but usually are of such character as to have a stimulating effect upon the average person of health; and it is not at all improbable that the great energy of its people, which has resulted in the rapid upbuilding of Chicago, is due largely to the peculiar nature of its climate.”

Excerpt from The Weather and Climate of Chicago, The Geographic Society of Chicago, Bulletin No. 4, H.J. Cox and J.H. Armington, University of Chicago Press, 1913.

Note: Google Books has the 1913 “The Weather and Climate of Chicago” by Cox and Armington and the more rare 1893 “The Climate of Chicago” by Hazen.