The statewide average precipitation was 1.38 inches, based on preliminary data. It was the third driest August on record and 2.22 inches below the 1981-2010 average.
Even though last year was remembered for the severe drought, the August 2012 precipitation was 3.64 inches and 0.04 inches above average.
The August 2013 precipitation and percent of average are posted below. The only areas with significant precipitation were far southern Illinois and a portion of northeastern Illinois. Elsewhere, precipitation amounts were far below average. A few areas in western Illinois received less than 0.1 inches.
Five Driest Augusts on Record:
- 1953 with 1.12 inches
- 1897 with 1.14 inches
- 2013 with 1.38 inches (preliminary)
- 1984 with 1.69 inches
- 1922 with 1.73 inches
The statewide average temperature was 73.1 degrees, which is only 0.4 degrees below average. August was noteworthy for being much below average for the first half of the month and much above average for the later half, effectively cancelling each other out by the end of the month.
Summer (June, July, and August)
The statewide average precipitation for summer was 9.93 inches, which is 1.92 inches below average. While June was above average (5.41 inches), both July (3.14 inches) and August (1.38 inches) were below average. It was an improvement over last summer when the average precipitation for the summer was 6.92 inches, 4.93 inches below the 1981-2010 average.
The statewide average temperature for this summer was 72.5 degrees, 1.1 degrees below the 1981-2010 average. June, July, and August were all below average but July had the coolest departure of 2.4 degrees below average.
Year to Date (January through August)
The statewide average precipitation for 2013 so far was 33.48 inches, which was 6.0 inches above the 1981-2010 average. This was far higher than last year when the statewide precipitation was only 17.79 inches through the end of August – almost half of this year.
The statewide average temperature for 2013 so far was 46.3 degrees, which was 1.2 degrees below the 1981-2010 average. This was far cooler than last year when the statewide temperature was 52.7 degrees, 5.2 degrees above average.