The statewide average precipitation for June 2013 in Illinois was 5.2 inches, which is nearly 1 inch above the 1981–2010 average. It was more than double the June 2012 total of 1.8 inches, according to Illinois State Climatologist Jim Angel, at the Illinois State Water Survey, Prairie Research Institute, University of Illinois.

The two wettest areas in Illinois were in northern Illinois and an area just south of Interstate 70. The highest monthly total in the state was Flora with 12.63 inches.

The area in northern Illinois was part of a larger area of heavy precipitation amounts in northeastern Iowa and southern Wisconsin. The area in southern Illinois extended into southern Indiana and Kentucky. Both regions had rainfall totals in excess of 8 inches and even 10 or more inches in some locations.

Most of the remainder of the state had close to average precipitation for June with 3 to 6 inches. The Midwest in general experienced a wet June, including the Ohio River Valley, which experienced drier conditions early in the month.

The year-to-date (January–June) statewide precipitation for Illinois was 28.7 inches, which was 8.9 inches above average and the wettest January–June on record. It is more than double the 12.7 inches accumulate in January–June of 2012 during the height of the drought.

The statewide average temperature in June was 71.5 degrees, which was 0.3 degrees below average.