A dry October in Illinois
The statewide average precipitation for October in Illinois was 1.79 inches, 1.12 below average. This was the 21st driest October on record for the state, according to Illinois State Climatologist Jim Angel at the Illinois State Water Survey, University of Illinois at Urbana-Champaign.
Rainfall amounts of less than one inch were common in western Illinois. The driest spot in the state was Colchester (near Macomb) with 0.22 inches for the month. The wettest spot was Lansing, south of Chicago, with 5.22 inches for October.
The average temperature for October was 55.1 degrees, just 0.5 degrees above average. The highest temperature was reported at Bentley with 92 degrees on October 8. The lowest temperature was 23 degrees at Mt. Carroll on October 29. Most of Illinois experienced temperatures at or below freezing by the end of the month.
No measurable snowfall was reported at any site in the state. That may change in November. The new 1981–2010 normals reveal that the average snowfall for the month ranges from 1 to 2 inches north of I-80, 0.5 to 1 inches between I-70 and I-80, and 0 to 0.5 inches south of I-70.
The Illinois State Water Survey at the University of Illinois at Urbana-Champaign, a division of the Prairie Research Institute, is the primary agency in Illinois concerned with water and atmospheric resources.