Shae Cohan photographed these sprites on August 26. Sprites are electrical discharges that occur above thunderstorms, typically at an altitude of 30 to 55 miles. The picture was taken from Macomb, although the storms in question were southeast of Springfield near Taylorville. (click image to enlarge)
A low temperature of 37 degrees in Champaign set an August record low, which still stands. Weather records in Champaign began in 1889.
Thunderstorms developed over northern Illinois during the evening hours. A series of thunderstorms moved across northern Cook County, dumping torrential amounts of rainfall. O'Hare Airport received 4.31 inches of rain, most of which fell between 9 pm and 11 pm. This rainfall brought the total for the month to 12.25 inches, making this the second wettest month on record for Chicago.