The reports are in and this July was the third wettest July on record for Illinois. The statewide average rainfall was 7.12 inches, 3.04 inches above normal. The largest rainfall total in the state was Carbondale with 13.34 inches. I just received word the Water Survey’s ICN gauge at Dixon Springs reported 16.42″ for July.
On a lesser note, the statewide average temperature for July was 75.9 degrees, 0.5 degrees above normal. While the second half of July was hot and humid, the first half had stretches of cool weather, including the July 4th weekend.
July Rainfall Ranked
Here are the top ten wettest Julys on record:
- 1958 with 8.10″
- 1992 with 7.61″
- 2016 with 7.12
- 1915 with 6.73″
- 1993 with 6.61″
- 1981 with 6.46″
- 1969 with 6.31″
- 1896 with 6.11″
- 1907 with 5.97″
- 2008 with 5.91″
Below are the rainfall totals and departures from normal for July. Illinois was pretty much blue all over, meaning most of the rainfall totals were 5 inches or more. The darkest shade of blue shows areas with 5 to 7.5 inches. The lighter shades of blue showed areas with 7.5 to 12.5 inches. A few stations reported more than 12.5 inches. The wettest site for July was Carbondale with 13.34 inches, followed by Downers Grove with 12.95 inches, Rosiclares with 12.94 inches, Godfrey with 12.75 inches, and Greenfield with 12.55 inches.
Rainfall Maps Using Radar/Rain Gauge Network
Here is an alternate view of the rainfall pattern over IL using a different technique, combining radar estimates and rain gauge measurements. Anything in red is over 5 inches. Anything in pink is 10-15 inches inches. In the bottom panel, there is some purple which corresponds to 15-20 inches. The Dixon Springs gauge with 16.42 inches is located in the purple area in Pope County. This set of maps shows more areas with less than 5 inches throughout the state.